HTMLgen.py

    #'$Id: HTMLgen.py,v 2.5 1999/04/20 03:29:14 friedric Exp friedric $'

    # COPYRIGHT (C) 1996-9  ROBIN FRIEDRICH  email:Robin.Friedrich@pdq.net
    # Permission to use, copy, modify, and distribute this software and
    # its documentation for any purpose and without fee is hereby granted,
    # provided that the above copyright notice appear in all copies and
    # that both that copyright notice and this permission notice appear in
    # supporting documentation.
    # THE AUTHOR DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS
    # SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND
    # FITNESS, IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
    # SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER
    # RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF
    # CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
    # CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.

    """A class library for the generation of HTML documents.

    Each HTML tag type has a supporting class which is responsible for
    emitting itself as valid HTML formatted text. An attempt is made to
    provide classes for newer HTML 3.2 and proposed tag elements.  The
    definitive reference for HTML tag elements can be found at
    [W3C].  Also, I used the HTML book by Musciano and
    Kennedy from [O Reilly] (2nd. Ed.) as the guiding reference.

    The Document classes are container objects which act as a focal point
    to populate all the contents of a particular web page. It also can
    enforce consistent document formating according to the guidelines from
    the [Yale Web Style Manual].

    Features include customization of document template graphics / colors
    through use of resource files, minimizing the need for modifying or
    subclassing from the module source code. Support for tables, frames,
    forms (persistent and otherwise) and client-side imagemaps are included.

    A newer implementation for the Table support is now included,
    TableLite().  In support of this there are new tag classes TD, TH, TR
    and Caption.  These class instances can be assembled in any way to
    populate the TableLite container object.

    .. [W3C] http://www.W3.org/TR/REC-html32.html
    .. [O Reilly] http://www.oreilly.com/catalog/html3/index.html
    .. [Yale Web Style Manual] http://info.med.yale.edu/caim/manual/contents.html
    """

    import string, re, time, os
    import UserList, copy
    from imgsize import imgsize

    __author__ = 'Robin Friedrich   friedrich@pythonpros.com'
    __version__ = '2.2.2'

    StringType = type('s')
    IntType    = type(3)
    ListType   = type([1])
    TupleType  = type((1,2))
    InstanceType = type(UserList.UserList())
    CONTYPE = 'Content-Type: text/html\n\n'
    DOCTYPE = '<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 3.2//EN">\n<HTML>\n'
    PRINTECHO = 1

    #################
    # CLASS LIBRARY #
    #################

    #======= NEW CLASS STRUCTURE ============
    # HTMLgen 1       HTMLgen 2
    # --------------- ------------------
    # Document        SeriesDocument
    # MinimalDocument SimpleDocument
    #                 BasicDocument (base class)
    #                 TemplateDocument

    class BasicDocument:
        """Base class to define an HTML document.

        Non-keyword arguments are taken as the initial contents for this object.

        Keyword arguments:
            title -- HTML TITLE attribute for document
            bgcolor -- background color expressed in hex-triplet or names from HTMLcolors.
            background -- background image filename
            cgi -- flag to indicate if this is used in CGI context (1 if it is)
            textcolor -- color to use for normal text
            linkcolor -- color to use for hyperlinks
            vlinkcolor -- color to use for visited hyperlinks
            alinkcolor -- color to use when hyperlink is active
        """
        title = ''
        cgi = None
        bgcolor = None
        background = None
        textcolor = None
        linkcolor = None
        vlinkcolor = None
        alinkcolor = None

        def __init__(self, *args, **kw):
            self.contents = list(args)
            for name, value in kw.items():
                setattr(self, name, value)

        def __str__(self):
            s = []
            if self.cgi:
                s.append('Content-Type: text/html\n\n' + DOCTYPE)
            else:
                s.append(DOCTYPE)
            s.append('\n<!-- This file generated using Python HTMLgen module. -->\n')

            # build the HEAD and BODY tags
            s.append(self.html_head())
            s.append(self.html_body_tag())

            # DOCUMENT CONTENT SECTION and FOOTER added on
            bodystring = '%s\n' * len(self.contents)
            s.append((bodystring % tuple(self.contents)))

            # CLOSE the document
            s.append('\n</BODY> </HTML>\n')
            return string.join(s, '')

        def html_head(self):
            """Generate the HEAD, TITLE and BODY tags.
            """
            return '\n  \n\
            %s \n' % (__version__, self.title)

        def html_body_tag(self):
            """Return BODY tag with attributes.
            """
            s = ['<BODY']
            if self.bgcolor:    s.append(' BGCOLOR="%s"' % self.bgcolor)
            if self.background: s.append(' BACKGROUND="%s"' % self.background)
            if self.textcolor:  s.append(' TEXT="%s"' % self.textcolor)
            if self.linkcolor:  s.append(' LINK="%s"' % self.linkcolor)
            if self.vlinkcolor: s.append(' VLINK="%s"' % self.vlinkcolor)
            if self.alinkcolor: s.append(' ALINK="%s"' % self.alinkcolor)
            s.append('>\n')
            return string.join(s, '')

        def append_file(self, filename, marker_function = None):
            """Add the contents of a file to the document.

            filename -- the filename of the file to be read [string]
            marker_function -- a callable object which the text read from
              the file will be passed through before being added to the
              document.
            """
            f = open(mpath(filename), 'r')
            if marker_function:
                self.append(marker_function(f.read()))
            else:
                self.append(f.read())
            f.close()

        def append(self, *items):
            """Add content to the Document object.

            Arg *items* can be plain text or objects; multiple arguments supported.
            """
            for item in items:
                self.contents.append(item)

        def prepend(self, *items):
            """Add content to the beginning of the Document object.

            Arg *items* can be plain text or objects; multiple arguments supported.
            """
            for item in items:
                self.contents.insert(0, item)

        def copy(self):
            """Return a complete copy of the current Document object.
            """
            return copy.deepcopy(self)

        def write(self, filename = None):
            """Emit the Document HTML to a file or standard output.

            In Unix you can use environment variables in filenames.
            Will print to stdout if no argument.
            """
            if filename:
                f = open(mpath(filename), 'w')
                f.write(str(self))
                f.close()
                if PRINTECHO: print 'wrote: "'+filename+'"'
            else:
                import sys
                sys.stdout.write(str(self))

    class FramesetDocument(BasicDocument):
        """A minimal document suitable for entering Framesets.

        Arguments are for contents **NOT** a document resource file.

        Keyword Parameters

            title -- string to be used as the document title.
            base  -- object of the Base class
            meta  -- object of the Meta class
            cgi   -- if non zero will issue a mime type of text/html
            script -- a single or list of Script objects to be included in the <HEAD>

        No <body> markup. Instead add Frameset(s) with the constructor or
        append method.
        """
        base = None
        meta = None
        cgi = None
        script = None

        def __str__(self):
            s = []
            if self.cgi:
                s.append('Content-Type: text/html\n\n' + DOCTYPE)
            else:
                s.append(DOCTYPE)
            s.append('\n<!-- This file generated using Python HTMLgen module. -->\n')

            # build the HEAD tag
            s.append(self.html_head())

            # DOCUMENT CONTENT SECTION
            bodystring = '%s\n' * len(self.contents)
            s.append((bodystring % tuple(self.contents)))

            # CLOSE the document
            s.append('\n</HTML>')
            return string.join(s, '')

    class SimpleDocument(BasicDocument):
        """Supports all features of a self contained document.

        This includes support for CSS1, meta and base tags, and embedded
        scripts.

        First constructor argument is resource file containing document
        attribute settings.
        """
        base = None
        style = None
        stylesheet = None
        meta = None
        onLoad = None
        onUnload = None
        script = None

        def __init__(self, resource = None, **kw):
            self.contents = []
            # Read attributes from resource file into instance namespace
            if resource: execfile(mpath(resource), self.__dict__)
            for name, value in kw.items():
                setattr(self, name, value)

        def __str__(self):
            s = []
            if self.cgi:
                s.append('Content-Type: text/html\n\n' + DOCTYPE)
            else:
                s.append(DOCTYPE)
            s.append('\n<!-- This file generated using Python HTMLgen module. -->\n')

            # build the HEAD and BODY tags
            s.append(self.html_head())
            s.append(self.html_body_tag())

            # DOCUMENT CONTENT SECTION and FOOTER added on
            bodystring = '%s\n' * len(self.contents)
            s.append((bodystring % tuple(self.contents)))

            s.append('\n</BODY> </HTML>\n') # CLOSE the document
            return string.join(s, '')

        def html_head(self):
            """Generate the HEAD TITLE and BODY tags.
            """
            s = ['\n  \n\
            %s\n' % (__version__, self.title)]
            if self.meta: s.append(str(self.meta))
            if self.base: s.append(str(self.base))
            if self.stylesheet:
                s.append('\n <LINK rel=stylesheet href="%s" type=text/css title="%s">\n' \
                         % (self.stylesheet, self.stylesheet))
            if self.style:
                s.append('\n<STYLE>\n<!--\n%s\n-->\n</style>\n' % self.style)
            if self.script: # for javascripts
                if type(self.script) in (TupleType, ListType):
                    for script in self.script:
                        s.append(str(script))
                else:
                    s.append(str(self.script))
            s.append('</HEAD>\n')
            return string.join(s, '')

        def html_body_tag(self):
            """Return BODY tag with attributes.
            """
            s = ['<BODY']
            if self.bgcolor:    s.append(' BGCOLOR="%s"' % self.bgcolor)
            if self.background: s.append(' BACKGROUND="%s"' % self.background)
            if self.textcolor:  s.append(' TEXT="%s"' % self.textcolor)
            if self.linkcolor:  s.append(' LINK="%s"' % self.linkcolor)
            if self.vlinkcolor: s.append(' VLINK="%s"' % self.vlinkcolor)
            if self.alinkcolor: s.append(' ALINK="%s"' % self.alinkcolor)
            if self.onLoad:     s.append(' onLoad="%s"' % self.onLoad)
            if self.onUnload:   s.append(' onUnload="%s"' % self.onUnload)
            s.append('>\n')
            return string.join(s, '')

    class SeriesDocument(SimpleDocument):
        """Primary container class for an HTML document as part of a series.

        Formerly known as Document().

        Navigation mechanisms are provided.

        Single optional string argument for the path to a resource file
        used to specify document parameters. This helps minimize the need
        for subclassing from this class. Keyword parameters may be used
        for any of the following class attributes. See *HTMLtest.py* for
        example usage.

        Class instance attributes and keyword arguments

            base -- object of the Base class
            meta -- object of the Meta class
            cgi  -- if non zero will issue a mime type of text/html
            logo -- ('filename', width, height)  All images are specified
                     with a tuple of string, int, int. If the size of the
                     graphic is unknown, use 0, 0.  This one is the little
                     graphic on the footer of each page.
            banner -- ('filename', width, height) Banner graphic at
                     the top of page. Can also be set to a string filename
                     or an Image object. Can be autosized if it's a GIF.
            title --  string to be used as the document title.
            subtitle -- string to be used as the document subtitle.
                     If non-nil, this string will be used for the doc title
                     instead of title.
            author -- String used in the copyright notice
            email -- Email address for feedback mailto: tag
            zone -- string used to label the time zone if datetime
                     is used. By default not used.
            bgcolor -- Color string (can use variables from
                     HTMLcolors.py)
            background -- string filename of a graphic used as the
                     doc background.
            textcolor -- Color string used for text.  (can use
                     variables from HTMLcolors.py)
            linkcolor -- Color string used for hyperlinked text.
            vlinkcolor -- Color string used for visited hypertext.
            alinkcolor -- Color string used for active hypertext.
            place_nav_buttons -- Flag to enable/disable the use of
                     navigation buttons.
                     Default is on. Set to 0 to disable.
            blank -- Image tuple for the transparent spacer gif
            prev -- Image tuple for the Previous Page button
            next -- Image tuple for the Next Page button
            top -- Image tuple for the Top of Manual button
            home -- Image tuple for the site Home Page button
            goprev -- URL string for the prev button
            gonext -- URL string for the next button
            gotop  -- URL string for the top button
            gohome -- URL string for the home button
            script -- a single or list of Script objects to be included in the
            onLoad -- Script, which is executed when the document is loaded
            onUnload -- Script, which is executed when the document is unloaded
        """
        subtitle = None
        banner = ('/image/banner.gif', 472, 30)
        logo = ('/image/logo.gif', 36, 35)
        author = 'Micky Mouse'
        email = 'micky@disney.com'
        zone = ' Central US'
        place_nav_buttons = 'yes'
        blank = ('../image/blank.gif', 71, 19)
        prev = ('../image/BTN_PrevPage.gif', 71, 19)
        next = ('../image/BTN_NextPage.gif', 71, 19)
        top = ('../image/BTN_ManualTop.gif', 74, 19)
        home = ('../image/BTN_HomePage.gif', 74, 19)
        goprev = None # URLs for above navigation buttons
        gonext = None
        gotop  = None
        gohome = None

        def __str__(self):
            s = []
            if self.cgi:
                s.append(CONTYPE + DOCTYPE)
            else:
                s.append(DOCTYPE)
            s.append('\n<!-- This file generated using Python HTMLgen module. -->\n')
            # build the HEAD and BODY tags
            s.append(self.html_head())
            s.append(self.html_body_tag())
            # HEADER SECTION
            s.append(self.header())

            # DOCUMENT CONTENT SECTION and FOOTER added on
            bodystring = '%s\n' * len(self.contents)
            s.append((bodystring % tuple(self.contents)))

            s.append(self.footer())
            s.append('\n</BODY> </HTML>\n') # CLOSE the document
            return string.join(s, '')

        def header(self):
            """Generate the standard header markups.
            """
            # HEADER SECTION - overload this if you don't like mine.
            s = []
            if self.banner:
                bannertype = type(self.banner)
                if bannertype in (TupleType, StringType):
                    s.append(str(Image(self.banner, border=0)) + '<BR>\n')
                elif bannertype == InstanceType:
                    s.append(str(self.banner) + '<BR>\n')
                else:
                    raise TypeError, 'banner must be either a tuple, instance, or string.'
            if self.place_nav_buttons:
                s.append(self.nav_buttons())
            s.append(str(Heading(3,self.title)))
            if self.subtitle:
                s.append('<H2>%s</H2>\n' % self.subtitle)
            s.append('<HR>\n\n')
            return string.join(s, '')

        def nav_buttons(self):
            """Generate hyperlinked navigation buttons.

            If a self.go* attribute is null that corresponding button is
            replaced with a transparent gif to properly space the remaining
            buttons.
            """
            s = []
            if self.goprev: # place an image button for previous page
                btn = Image(self.prev, border=0, alt='Previous')
                link = Href(self.goprev, str(btn))
                s.append(str(link) + ' \n')
            else: # place a blank gif as spacer
                #btn = Image(self.blank)
                s.append('<span style="width: 60px"></span> \n')
            if self.gonext: # place an image button for next page
                btn = Image(self.next, border=0, alt='Next')
                link = Href(self.gonext, str(btn))
                s.append(str(link) + ' \n')
            else: # place a blank gif as spacer
                btn = Image(self.blank)
                s.append(str(btn) + ' \n')
            if self.gotop: # place an image button for top of manual page
                btn = Image(self.top, border=0, alt='Top of Manual')
                link = Href(self.gotop, str(btn))
                s.append(str(link) + ' \n')
            else: # place a blank gif as spacer
                btn = Image(self.blank)
                s.append(str(btn) + ' \n')
            if self.gohome: # place an image button for site home page
                btn = Image(self.home, border=0, alt='Home Page')
                link = Href(self.gohome, str(btn))
                s.append(str(link) + ' \n')
            else: # place a blank gif as spacer
                btn = Image(self.blank)
                s.append(str(btn) + ' \n')
            return string.join(s, '')

        def footer(self):
            """Generate the standard footer markups.
            """
            # FOOTER SECTION - overload this if you don't like mine.
            t = time.localtime(time.time())
            #self.datetime = time.strftime("%c %Z", t)    #not available in JPython
            self.datetime = time.asctime(t)
            #self.date = time.strftime("%A %B %d, %Y", t)
            x = string.split(self.datetime)
            self.date = x[0] + ' ' + x[1] + ' ' + x[2] + ', ' + x[4]
            s =  ['\n<P><HR>\n']
            if self.place_nav_buttons:
                s.append(self.nav_buttons())
            s.append('<BR>' + str(Image(self.logo, align='bottom')))
            s.append('\nCopyright © %s
    All Rights Reserved
    \n' \
                % self.author)
            s.append('\nComments to author: ' + str(MailTo(self.email)) )
            s.append('<br>\nGenerated: %s <BR>' % self.date) # can use self.datetime here instead
            s.append('\n')
            return string.join(s, '')

    # Aliases for backward compatability with HTMLgen 1.2
    Document = SeriesDocument
    MinimalDocument = SimpleDocument

    class StringTemplate:
        """Generate documents based on a template and a substitution mapping.

        Must use Python 1.5 or newer. Uses re and the get method on dictionaries.

        Usage:
           T = TemplateDocument('Xfile')
           T.substitutions = {'month': ObjectY, 'town': 'Scarborough'}
           T.write('Maine.html')

        A dictionary, or object that behaves like a dictionary, is assigned to the
        *substitutions* attribute which has symbols as keys to objects. Upon every
        occurance of these symbols surrounded by braces {} in the source template,
        the corresponding value is converted to a string and substituted in the output.

        For example, source text which looks like:
         I lost my heart at {town} Fair.
        becomes:
         I lost my heart at Scarborough Fair.

        Symbols in braces which do not correspond to a key in the dictionary remain
        unchanged.

        An optional third argument to the class is a list or two strings to be
        used as the delimiters instead of { } braces. They must be of the same
        length; for example ['##+', '##'] is invalid.
        """
        def __init__(self, template, substitutions=None, **kw):
            self.delimiters = ['{', '}']
            self.__dict__.update(kw)
            if len(self.delimiters) != 2:
                raise ValueError("delimiter argument must be a pair of strings")
            self.delimiter_width = len(self.delimiters[0])
            delimiters = map(re.escape, self.delimiters)
            self.subpatstr = delimiters[0] + "[\w_]+" + delimiters[1]
            self.subpat = re.compile(self.subpatstr)
            self.substitutions = substitutions or {}
            self.set_template(template)

        def set_template(self, template):
            self.source = template

        def keys(self):
            return self.substitutions.keys()

        def __setitem__(self, name, value):
            self.substitutions[name] = value

        def __getitem__(self, name):
            return self.substitutions[name]

        def __str__(self):
            return self._sub(self.source)

        def _sub(self, source, subs=None):
            """Perform source text substitutions.

            *source* string containing template source text
            *subs* mapping of symbols to replacement values
            """
            substitutions = subs or self.substitutions
            dw = self.delimiter_width
            i = 0
            output = []
            matched = self.subpat.search(source[i:])
            while matched:
                a, b = matched.span()
                output.append(source[i:i+a])
                # using the new get method for dicts in 1.5
                output.append(str(substitutions.get(
                       source[i+a+dw:i+b-dw], source[i+a:i+b])))
                i = i + b
                matched = self.subpat.search(source[i:])
            else:
                output.append(source[i:])
            return string.join(output, '')

        def write(self, filename = None):
            """Emit the Document HTML to a file or standard output.

            Will not overwrite file is it exists and is textually the same.
            In Unix you can use environment variables in filenames.
            Will print to stdout if no argument given.
            """
            if filename:
                filename = mpath(filename)
                if os.path.exists(filename):
                    s = str(self)
                    if compare_s2f(s, filename):
                        f = open(filename, 'w')
                        f.write(str(self))
                        f.close()
                        if PRINTECHO: print 'wrote: "'+filename+'"'
                    else:
                        if PRINTECHO: print 'file unchanged: "'+filename+'"'
                else:
                    f = open(filename, 'w')
                    f.write(str(self))
                    f.close()
                    if PRINTECHO: print 'wrote: "'+filename+'"'
            else:
                import sys
                sys.stdout.write(str(self))

    class TemplateDocument(StringTemplate):
        """Generate documents based on a template and a substitution mapping.

        Must use Python 1.5 or newer. Uses re and the get method on dictionaries.

        Usage:
           T = TemplateDocument('Xfile')
           T.substitutions = {'month': ObjectY, 'town': 'Scarborough'}
           T.write('Maine.html')

        A dictionary, or object that behaves like a dictionary, is assigned to the
        *substitutions* attribute which has symbols as keys to objects. Upon every
        occurance of these symbols surrounded by braces {} in the source template,
        the corresponding value is converted to a string and substituted in the output.

        For example, source text which looks like:
         I lost my heart at {town} Fair.
        becomes:
         I lost my heart at Scarborough Fair.

        Symbols in braces which do not correspond to a key in the dictionary remain
        unchanged.

        An optional third argument to the class is a list or two strings to be
        used as the delimiters instead of { } braces. They must be of the same
        length; for example ['##+', '##'] is invalid.
        """
        def set_template(self, template):
            f = open(mpath(template))
            self.source = f.read()
            f.close()

    class AutoStringTemplate(StringTemplate):
        marker_begin = '<!--{%s}Begin-->'
        marker_end   = '<!--{%s}End-->'
        R = re.compile(r"(?P.*?)", re.S)

        def set_template(self, template):
            """Set template string and normalize by extracting comment tokens.
            """
            self.source = template
            self.extract_template()

        def extract_template(self, source=None):
            """Convert comment-marked regions to a regular {tokens}.

            Updates the substitution dictionary with the text from the region.
            """
            source = source or self.source
            a = 0
            newsubs = {}
            newtemplate = []
            d1, d2 = self.delimiters
            while 1:
                m = self.R.search(source, a)
                if m:
                    start, end = m.span()
                    newtemplate.append(source[a:start])
                    a = end
                    newsubs[m.group('key')] = m.group('text')
                    newtemplate.append(d1+m.group('key')+d2)
                else:
                    newtemplate.append(source[a:])
                    break
            self.source = string.join(newtemplate, '')
            self.substitutions.update(newsubs)

        def _sub(self, source, subs=None):
            """Perform source text substitutions.

            *source* string containing template source text
            *subs* mapping of symbols to replacement values
            """
            substitutions = subs or self.substitutions
            dw = self.delimiter_width
            i = 0
            output = []
            matched = self.subpat.search(source[i:])
            while matched:
                a, b = matched.span()
                output.append(source[i:i+a])
                #implant comments to mark the location of the tokens
                output.append(self.marker_begin % source[i+a+dw:i+b-dw])
                # using the new get method for dicts in 1.5
                output.append(str(substitutions.get(
                       source[i+a+dw:i+b-dw], source[i+a:i+b])))
                output.append(self.marker_end % source[i+a+dw:i+b-dw])
                i = i + b
                matched = self.subpat.search(source[i:])
            else:
                output.append(source[i:])
            return string.join(output, '')

    class AutoTemplateDocument(AutoStringTemplate):
        """Generate documents based on a template and a substitution mapping.

        The primary difference between AutoTemplateDocument and TemplateDocument
        is that the Auto version can read through an HTML file previously
        generated with this class and identify the regions of text that were
        substituted. It then extracts that text into the substitution dictionary
        and can then be updated. The intent is to eliminate the need to
        maintain separate content files for insertion into templates. The HTML
        output file can double as a template for future use.
        Output from this class have their filled regions marked by comments:
            ...gets glued, in place...
        Which came from ...gets {wz} in place... in old style template syntax.

        AutoTemplateDocument is a functional superset of TemplateDocument and should
        be compatible.

        Usage:
           T = AutoTemplateDocument('Maine.html')
           T.substitutions = {'month': ObjectY, 'town': 'Scarborough'}
           or
           T['month'] = ObjectY ; T['town'] = 'Scarborough'
           T.write('Maine.html')

        A dictionary, or object that behaves like a dictionary, is assigned to the
        *substitutions* attribute which has symbols as keys to objects. Upon every
        occurance of these symbols surrounded by braces {} in the source template,
        the corresponding value is converted to a string and substituted in the output.

        For example, source text which looks like:
         I lost my heart at {town} Fair.
        becomes:
         I lost my heart at Scarborough Fair.

        Symbols in braces which do not correspond to a key in the dictionary remain
        unchanged.

        An optional third argument to the class is a list or two strings to be
        used as the delimiters instead of { } braces. They must be of the same
        length; for example ['##+', '##'] is invalid.
        """
        def set_template(self, template):
            f = open(mpath(template))
            self.source = f.read()
            f.close()

    class Container:
        """A holder for a list of HTMLgen objects.
        """

        def __init__(self, *args, **kw):
            self.contents = list(args)
            for name, value in kw.items():
                setattr(self, name, value)

        def __str__(self):
            bodystring = '%s\n' * len(self.contents)
            return bodystring % tuple(self.contents)

        def __add__(self, other):
            new = self.__class__()
            new.contents = self.contents + other.contents
            return new

        def append_file(self, filename, marker_function = None):
            """Add the contents of a file to the document.

            filename -- the filename of the file to be read [string]
            marker_function -- a callable object which the text read from
              the file will be passed through before being added to the
              document.
            """
            f = open(mpath(filename), 'r')
            if marker_function:
                self.append(marker_function(f.read()))
            else:
                self.append(f.read())
            f.close()

        def append(self, *items):
            """Add content to the Document object.

            Arg *items* can be plain text or objects; multiple arguments supported.
            """
            for item in items:
                self.contents.append(item)

        def prepend(self, *items):
            """Add content to the beginning of the Document object.

            Arg *items* can be plain text or objects; multiple arguments supported.
            """
            li = len(items)
            for i in range(li-1, 0, -1):
                self.contents.insert(0, items[i])

        def copy(self):
            """Return a complete copy of the current Container object.
            """
            return copy.deepcopy(self)

    #===================

    class Meta:
        """Set document Meta-information.

        The META element is used within the HEAD element to embed
        document meta-information not defined by other HTML elements.

        Keywords supported

            name  -- NAME element attribute (default: 'keywords')
            equiv  -- will map to the HTTP-EQUIV attribute
            content -- mandatory attribute (default: 'python,HTMLgen')
            url -- URL naturally

        Example:

            Meta( name='keywords', content='eggs,spam,beans' )
        """
        def __init__(self, **kw):
            self.equiv = 'keywords'
            self.name  = ''
            self.content = 'python,HTMLgen'
            self.url = ''
            for item in kw.keys():
                self.__dict__[item] = kw[item]

        def __str__(self):
            s = ['<META']
            if self.equiv: s.append(' HTTP-EQUIV="%s"' % self.equiv)
            if self.name:  s.append(' NAME="%s"' % self.name)
            if self.content: s.append(' CONTENT="%s"' % self.content)
            if self.url: s.append(' URL="%s"' % self.url)
            s.append('>\n')
            return string.join(s, '')

    ##### Client-side Imagemap Support #####

    class Map:
        """Used to name and describe a client-side image map.

        The *areas* argument is a list of Area objects.
        Keyword arg is supported for *name*, which defines the map name
        to be used with the usemap attribute of an Image class instance.
        """
        def __init__(self, areas = None, **kw):
            self.areas = areas or []
            self.name = ''
            for item in kw.keys():
                self.__dict__[item] = kw[item]

        def __str__(self):
            s = ['\n<MAP NAME="%s">\n' % self.name]
            for area in self.areas:
                s.append(str(area))
            s.append('</MAP>\n')
            return string.join(s, '')

    class Href:
        """Generate a hyperlink.

        Argument 1 is the URL and argument 2 is the hyperlink text.

        Keyword arguments

            target -- is an optional target symbol
            onClick --  is the script-code which is executed when link is clicked.
            onMouseOver -- the script-code which is executed when the mouse
                           moves over the link.
            onMouseOut -- the script-code which is executed when the mouse
                           moves off the link.
        """
        def __init__(self, url='', text='', **kw):
            self.target = None
            self.onClick = None
            self.onMouseOver = None
            self.onMouseOut = None
            self.url = url
            self.text = text
            for item in kw.keys():
                if self.__dict__.has_key(item):
                    self.__dict__[item] = kw[item]
                else:
                    raise KeyError, `item`+' not a valid parameter for this class.'

        def __str__(self):
            s = ['<A HREF="%s"' % self.url]
            if self.target: s.append(' TARGET="%s"' % self.target)
            if self.onClick: s.append(' onClick="%s"' % self.onClick)
            if self.onMouseOver: s.append(' onMouseOver="%s"' % self.onMouseOver)
            if self.onMouseOut: s.append(' onMouseOut="%s"' % self.onMouseOut)
            s.append('>%s</A>' % self.text)
            return string.join(s, '')

        def append(self, content):
            self.text = self.text + str(content)

    A = HREF = Href # alias

    class Name(Href):
        """Generate a named anchor.

        Arg *url* is a string or URL object,
        Arg *text* is optional string or object to be highlighted as the anchor.
        """
        def __str__(self):
            return '<A NAME="%s">%s</A>' % (self.url, self.text)

    NAME = Name # alias

    class MailTo:
        """A Mailto href

        First argument is an email address, optional second argument is
        the text shown as the underlined hyperlink. Default is the email
        address. Optional third argument is a Subject: for the email.
        """
        def __init__(self, address='', text=None, subject=None):
            self.address = address
            self.text = text or address
            self.subject = subject

        def __str__(self):
            if self.subject: self.address = "%s?subject=%s" % (self.address, self.subject)
            return '<A HREF="mailto:%s">%s</A>' % (self.antispam(self.address), self.text)

        def antispam(self, address):
            """Process a string with HTML encodings to defeat address spiders.
            """
            from whrandom import choice
            buffer = map(None, address)
            for i in range(0, len(address), choice((2,3,4))):
                buffer[i] = '&#%d;' % ord(buffer[i])
            return string.join(buffer,'')

    MAILTO = Mailto = MailTo # aliases

    class P:
        """Just echo a <P> tag."""
        def __str__(self):
            return '\n<P>\n'

    # List constructs

    class List(UserList.UserList):
        """Will generate a bulleted list given a list argument.

        Now supports rendering a list into multiple columns by setting the
        *columns* attribute to a number greater than one. This is
        implemented using tables and you can also set a background color
        for the list itself by using the *bgcolor* attribute.

        Supports nested lists, i.e. lists of lists. Each time a list is
        encountered in a list it will indent those contents w.r.t. the
        prior list entry. This can continue indefinitely through nested
        lists although there are only three different bullets provided by
        the browser (typically).

        Optional keyword *indent* can be used to indicate whether you want
        the list to start left justified or indented. *indent=0* will make
        it left justified. The default is to indent.

        Optional keyword *type* can be set to either disk, circle, or
        square to specify what kind of symbol is used for each list item's
        bullet. (Netscape extension)

        Since we inherit from the UserList class any normal list
        operations work on instances of this class.  Any list contents
        will do. Each of the items will be emitted in html if they are
        themselves objects from this module.
        Aliases: UL, BulletList
        """

        I_am_a_list = 1
        tagname = 'UL'
        attrs = ('type','align','class','id','style')
        flags = ('compact',)
        columns = 1
        bgcolor = ''
        pad = '    '
        indent = 1
        def __init__(self, list = None, **kw):
            self.data = []
            self.lvl = 0
            if list:
                if type(list) == type(self.data):
                    self.data[:] = list
                else:
                    self.data[:] = list.data[:]
            for item in kw.keys():
                self.__dict__[string.lower(item)] = kw[item]

        def __getslice__(self, i, j):
            newlist = copy.copy(self)
            newlist.data = self.data[i:j]
            newlist.columns = 1 # don't forget that the copy will carry
                                # the old attribute value. set to 1
            return newlist

        def multi_column_table(self):
            """Return a table containing the list sliced into columns.
            """
            slices = self.column_slices(self.columns)
            table = TableLite(border=0, cellpadding=3)
            if self.bgcolor: table.bgcolor = self.bgcolor
            for begin, end in slices:
                column = TD(self[begin:end], valign='top', html_escape='no')
                table.append(column)
            return table

        def column_slices(self, columns=1):
            """Calculate a list of index pairs bounding column slices.
            """
            list_len = len(self.data)
            col_len, remainder = divmod(list_len, columns)
            if remainder: col_len = col_len + 1
            indexpairs = []
            if columns > 1:
                for column in range(columns):
                    col_end = (column+1)*col_len
                    if col_end < list_len:
                        indexpairs.append((column*col_len, col_end))
                    else:
                        indexpairs.append((column*col_len, list_len))
            else:
                indexpairs.append((0, list_len))
            return indexpairs

        def __str__(self):
            if self.columns > 1: # go to the new multicolumn feature
                return str(self.multi_column_table())
            # same as before
            self.firstitem = 1
            self.s = []
            if self.indent:
                self.s.append(self.pad*self.lvl + self.start_element())
            for item in self.data: #start processing main list
                itemtype = type(item)
                if itemtype == InstanceType:
                    try: # in case it's a nested list object
                        if item.I_am_a_list:
                            itemtype = ListType
                    except AttributeError:
                        pass
                if itemtype == ListType: #process the sub list
                    self.sub_list(item)
                else:
                    self.s.append(self.render_list_item(item))

            if self.indent: #close out this level of list
                self.s.append(self.pad*self.lvl + self.end_element())
            self.lvl = 0
            return string.join(self.s, '')

        def sub_list(self, list):
            """Recursive method for generating a subordinate list
            """
            self.lvl = self.lvl + 1
            if type(list) == InstanceType:
                try:
                    if list.I_am_a_list: #render the List object
                        list.lvl = self.lvl
                        self.s.append(str(list))
                except AttributeError:
                    pass
            else:
                self.s.append(self.pad*self.lvl + self.start_element())
                for item in list:
                    itemtype = type(item)
                    if itemtype == InstanceType:
                        try: #could be another nested List child object
                            if item.I_am_a_list:
                                itemtype = ListType
                        except AttributeError:
                            pass
                    if itemtype == ListType:
                        self.sub_list(item) #recurse for sub lists
                    else: # or just render it
                        self.s.append(self.render_list_item(item))
                # close out this list level
                self.s.append(self.pad*self.lvl + self.end_element())
            self.lvl = self.lvl - 1 #decrement indentation level

        def render_list_item(self, item):
            """Renders the individual list items

            Overloaded by child classes to represent other list styles.
            """
            return '%s<LI>%s\n' % (self.pad*self.lvl, item)

        def start_element(self):
            """Generic creator for the HTML element opening tag.

            Reads tagname, attrs and flags to return appropriate tag.
            """
            s = ['<' + self.tagname]
            for attr in self.attrs:
                try:
                    s.append(' %s="%s"' % (attr, getattr(self, attr)))
                except AttributeError:
                    pass
            for flag in self.flags:
                try:
                    x = getattr(self, flag)
                    s.append(' %s' % flag)
                except AttributeError:
                    pass
            s.append('>\n')
            return string.join(s, '')

        def end_element(self):
            """Closes the HTML element
            """
            return '</%s>\n' % self.tagname

        def append(self, *items):
            """Append entries to the end of the list
            """
            for item in items:
                self.data.append(item)

    UL = BulletList = List  #Aliases

    class OrderedList(List):
        """Will generate a numbered list given a list arg.

        Optional keyword *type* can be used to specify whether you want
        the list items marked with: capital letters (type='A'), small
        letters (type='a'), large Roman numerals (type='I'), small Roman
        numerals (type='i'). The default is arabic numbers. The other
        types are HTML3.2 only and may not be supported by browsers yet.
        Any list contents will do. Each of the items will be emitted
        in HTML if they are themselves objects.
        """
        tagname = 'OL'
        attrs = ('type','class','id','style')

    OL = NumberedList = OrderedList

    class DefinitionList(List):
        """Show a series of items and item definitions.

        Arg is a list of tuple pairs:
        [(string/object,string/object),(,)...]  1st item in each pair is
        the word to be defined. It will be rendered in bold. 2nd is the
        string which will be indented to it's next-line-right. If the
        *compact* flag is set to non-empty, the definition side will be
        placed on the same line.  Example

            DefinitionList([( 4 , 'Number after 3') , ( 1 , 'Unity')] ) will emit:
            4
                Number after 3
            1
                Unity
        """
        tagname = 'DL'
        attrs = ('class','id','style')
        flags = ('compact',)
        def render_list_item(self, item):
            """Overload method to perform DT/DD markup.
            """
            return '%s<DT><B>%s</B><DD>%s\n' % (self.pad*self.lvl, item[0], item[1])

    DL = DefinitionList

    class ImageBulletList(List):
        """Show a list of images with adjoining text(or object).

        Arg is a list of tuple pairs: [(Image_obj, string/object),(,)...]
        Generates an inlined image then the text followed by a <BR>
        for each element.
        """
        tagname = 'UL'
        attrs = ()
        flags = ()
        def render_list_item(self, item):
            """Overload method to take first item from an item tuple and
            setting it next to the second item, using BR to separate list items.
            """
            return '%s%s %s<BR>\n' % (self.pad*self.lvl, item[0], item[1])

    class NonBulletList(List):
        """Generate a raw indented list without bullet symbols.

        Arg is a list of python objects:
        """
        tagname = 'UL'
        attrs = ()
        flags = ()
        def render_list_item(self, item):
            """Overload method to take first item from an item tuple and
            setting it next to the second item, using BR to separate list items.
            """
            return '%s%s<BR>\n' % (self.pad*self.lvl, item)

    ####### FORM TAGS ########
    class Form:
        """Define a user filled form. Uses POST method.

        *cgi* is the URL to the CGI processing program.  Input objects
        (any others as well) are appended to this container widget.

        Keywords

            name -- name of the form
            submit -- The Input object to be used as the submit button.
                      If none specified a Submit button will automatically
                      be appended to the form. Do not manually append your
                      submit button. HTMLgen will append it for you.
            reset  -- Input object to be used as a reset button.
            target -- set a TARGET attribute
            enctype -- specify an Encoding type.
            onSubmit -- script, which is executed, when the form is submitted
        """
        def __init__(self, cgi = None, **kw):
            self.contents = []
            self.cgi = cgi
            self.submit = Input(type='submit', name='SubmitButton', value='Send')
            self.reset = None
            self.target = None
            self.enctype = None
            self.name = None
            self.onSubmit = ''
            overlay_values(self, kw)

        def append(self, *items):
            """Append any number of items to the form container.
            """
            for item in items:
                self.contents.append(str(item))

        def __str__(self):
            s = ['\n<FORM METHOD="POST"']
            if self.cgi: s.append(' ACTION="%s"' % self.cgi)
            if self.enctype: s.append(' ENCTYPE="%s"' % self.enctype)
            if self.target: s.append(' TARGET="%s"' % self.target)
            if self.name: s.append(' NAME="%s"' % self.name)
            if self.onSubmit: s.append(' onSubmit="%s"' % self.onSubmit)
            s.append('>\n')
            s = s + self.contents
            s.append(str(self.submit))
            if self.reset: s.append(str(self.reset))
            s.append('\n</FORM>\n')
            return string.join(s, '')

    def overlay_values(obj, dict):
        """Adds each item from dict to the given object iff there already
        exists such a key. Raises KeyError if you try to update the value
        of non-existing keys.
        """
        for key in dict.keys():
            if hasattr(obj, key):
                obj.__dict__[key] = dict[key]
            else:
                raise KeyError(`key` + ' not a keyword for ' + obj.__class__.__name__)

    class Input:
        """General Form Input tags.

        Keyword Arguments

            type -- 'TEXT' (default) Supported types include password, checkbox,
                          radio, file, submit, reset, hidden.
            name -- provides the datum name
            value -- the initial value of the input item
            checked --  flag indicating if the item is checked initially
            size -- size of the widget (e.g. size=10 for a text widget is it's width)
            maxlength -- maximum number of characters accepted by the textfield.
            border -- border width in pixels for an image type.
            align -- top|middle|bottom align w.r.t. adjoining text for image types.
            llabel  --  an optional string set to the left of the widget
            rlabel  --  an optional string set to the right of the widget
            onBlur -- script, which is executed, when the field loses focus,
                      useful for the text-type
            onChange -- script, which is executed, when the field value changed,
                        useful for the text-type
            onClick -- script, which is executed, when the field in clicked,
                       useful for the button, checkbox, radio, submit, reset type
            onFocus -- script, which is executed, when the field receives focus,
                       useful for the text-type
            onSelect -- script, which is executed, when part of the field
                        is selected, useful for the text-type
        """
        re_type = re.compile('text|password|checkbox|radio|image|button|file|submit|reset|hidden',
                                re.IGNORECASE)
        def __init__(self, **kw):
            self.type = 'TEXT'
            self.name = 'Default_Name'
            self.value = None
            self.checked = ''
            self.size = 0
            self.maxlength = 0
            self.llabel = ''
            self.rlabel = ''
            self.onBlur = ''
            self.onChange = ''
            self.onClick = ''
            self.onFocus = ''
            self.onSelect = ''
            self.border = None
            self.align = ''
            for item in kw.keys():
                if self.__dict__.has_key(item):
                    self.__dict__[item] = kw[item]
                else:
                    raise KeyError, `item`+' not a valid parameter of the Input class.'
            if Input.re_type.search(self.type) is None:
                raise KeyError, `self.type`+' not a valid type of Input class.'

        def __str__(self):
            s = []
            if self.llabel: s.append(str(self.llabel))
            s.append('\n<INPUT')
            if self.type: s.append(' TYPE="%s"' % self.type)
            if self.name: s.append(' NAME="%s"' % self.name)
            if self.value is not None: s.append(' VALUE="%s"' % self.value)
            if self.checked: s.append(' CHECKED')
            if self.size: s.append(' SIZE=%s' % self.size)
            if self.maxlength: s.append(' MAXLENGTH=%s' % self.maxlength)
            if self.onBlur: s.append(' onBlur="%s"' % self.onBlur)
            if self.onChange: s.append(' onChange="%s"' % self.onChange)
            if self.onClick: s.append(' onClick="%s"' % self.onClick)
            if self.onFocus: s.append(' onFocus="%s"' % self.onFocus)
            if self.onSelect: s.append(' onSelect="%s"' % self.onSelect)
            if self.border is not None: s.append(' BORDER="%s"' % self.border)
            if self.align: s.append(' ALIGN="%s"' % self.align)
            s.append('>')
            if self.rlabel: s.append(str(self.rlabel))
            return string.join(s, '')

    class Select(UserList.UserList):
        """Used to define a list widget or option widget.

        Pass a list of strings to show a list with those values. Alternatively
        can pass a list of tuple pairs. Each pair contains the displayed string
        and it's associatated value mapping. If no value mapping is needed just
        use something that evaluates to None.

        Keyword Arguments:

            name -- provides the datum name
            size -- the visual size. 1 means use an option popup widget.
                                   >=2 means use a list widget with that many lines.
            multiple -- flag to indicate whether multiple selections are supported.
            selected -- list of values to be shown as pre-selected.
            onBlur -- script, which is executed, when the field loses focus
            onChange -- script, which is executed, when the field value changed
            onFocus -- script, which is executed, when the field receives focus
        """
        def __init__(self, data=None, **kw):
            UserList.UserList.__init__(self, data)
            self.name = ''
            self.size = 1
            self.multiple = None
            self.selected = []
            self.onBlur = ''
            self.onChange = ''
            self.onFocus = ''
            for item in kw.keys():
                if self.__dict__.has_key(item):
                    self.__dict__[item] = kw[item]
                else:
                    raise KeyError, `item`+' not a valid parameter of the Select class.'

        def __str__(self):
            s = ['<SELECT NAME="%s"' % self.name]
            if self.size: s.append(' SIZE=%s' % self.size)
            if self.multiple: s.append(' MULTIPLE')
            if self.onBlur: s.append(' onBlur="%s"' % self.onBlur)
            if self.onChange: s.append(' onChange="%s"' % self.onChange)
            if self.onFocus: s.append(' onFocus="%s"' % self.onFocus)
            s.append('>\n')
            if type(self.data[0]) is TupleType:
                for item, value in self.data:
                    s.append('<OPTION')
                    if value is not None:
                        s.append(' Value="%s"' % value)
                    if value in self.selected:
                        s.append(' SELECTED')
                    else:
                        if item in self.selected:
                            s.append(' SELECTED')
                    s.append('>%s\n' % item)
            else:
                for item in self.data:
                    if item not in self.selected:
                        s.append('<OPTION>%s\n' % item)
                    else:
                        s.append('<OPTION SELECTED>%s\n' % item)
            s.append('</SELECT>\n')
            return string.join(s, '')

    class Textarea:
        """Used for an entry widget to type multi-line text (for forms).

        Keyword Arguments:

            rows -- sets the number of text rows. (default=4)
            cols -- sets the number of text columns. (default=40)
            onBlur -- script, which is executed, when the field loses focus
            onChange -- script, which is executed, when the field value changed
            onFocus -- script, which is executed, when the field receives focus
            onSelect -- script, which is executed, when part of the field
                        is selected
        """
        def __init__(self, text='', **kw):
            self.text = text
            self.name = 'text_area'
            self.rows = 4
            self.cols = 40
            self.onBlur = ''
            self.onChange = ''
            self.onFocus = ''
            self.onSelect = ''
            for item in kw.keys():
                if self.__dict__.has_key(item):
                    self.__dict__[item] = kw[item]
                else:
                    raise KeyError, `item`+' not a valid parameter of the Textarea class.'

        def __str__(self):
            s = ['<TEXTAREA NAME="%s" ROWS=%s COLS=%s' % (self.name, self.rows, self.cols)]
            if self.onBlur: s.append(' onBlur="%s"' % self.onBlur)
            if self.onChange: s.append(' onChange="%s"' % self.onChange)
            if self.onFocus: s.append(' onFocus="%s"' % self.onFocus)
            if self.onSelect: s.append(' onSelect="%s"' % self.onSelect)
            s.append('>')
            s.append(str(self.text))
            s.append('</TEXTAREA>')
            return string.join(s, '')

    class Script:
        """Construct a Script

        Keyword Arguments

            Defaults in (parenthesis).  Keyword parameters may be set as attributes of
            the instantiated script object as well.

            language -- specifies the language ('JavaScript')
            src -- specifies the location
            code -- script code, which is printed in comments, to hide it from non
                    java-script browsers
        """
        def __init__(self, **kw):
            # Specify the default values
            self.language = 'JavaScript'
            self.src = ''
            self.code = ''
            # Now overlay the keyword arguments from caller
            for k in kw.keys():
                if self.__dict__.has_key(k):
                    self.__dict__[k] = kw[k]
                else:
                    print `k`, "isn't a valid parameter for this class."

        def __str__(self):
            s = ['<SCRIPT LANGUAGE="%s" ' % self.language]
            if self.src: s.append('SRC="%s" ' % self.src)
            s.append('>')
            if self.code: s.append('<!--\n%s\n//-->\n' % self.code)
            s.append('</SCRIPT>')
            return string.join(s, '')

        def append(self, s):
            self.code = self.code + s

    ####################

    class Table:
        """Construct a Table with Python lists.

        Instantiate with a string argument for the table's name (caption).
        Set object.heading to a list of strings representing the column headings.
        Set object.body to a list of lists representing rows. **WARNING:** the body
        attribute will be edited to conform to html. If you don't want your
        data changed make a copy of this list and use that with the table object.

        Keyword Parameters

            Defaults in (parenthesis).  Keyword parameters may be set as attributes of the
            instantiated table object as well.

            caption_align -- 'top'|'bottom'  specifies the location of the table title ('top')
            border -- the width in pixels of the bevel effect around the table (2)
            cell_padding -- the distance between cell text and the cell boundary (4)
            cell_spacing -- the width of the cell borders themselves (1)
            width -- the width of the entire table wrt the current window width ('100%')
            colspan -- a list specifying the number of columns spanned by that heading
                   index. e.g. t.colspan = [2,2] will place 2 headings spanning
                   2 columns each (assuming the body has 4 columns).
            heading --  list of strings, the length of which determine the number of
                       columns.  ( ['&nbsp']*3 )
            heading_align -- 'center'|'left'|'right'
                            horizontally align text in the header row ('center')
            heading_valign --  'middle' |'top'|'bottom'
                            vertically align text in the header row ('middle')
            body_color -- a list of colors, for each column (None)
            heading_color -- a list of color for each column heading (None)
                 For both these the index used is i%len(..._color) so
                 the color cycles through the columns
            body -- a list of lists in row major order containing strings or objects
                   to populate the body of the table. ( [['&nbsp']*3] )
            column1_align -- 'left'|'right'|'center'  text alignment of the first column
            cell_align --    'left'|'right'|'center'  text alignment for all other cells
            cell_line_breaks -- 1|0  flag to determine if newline char in body text will be
                      converted to
     symbols; 1 they will, 0 they won't. (1)

        """
        def __init__(self, tabletitle='', **kw):
            """Arg1 is a string title for the table caption, optional keyword
            arguments follow.
            """
            # Specify the default values
            self.tabletitle = tabletitle
            self.caption_align = 'top'
            self.border = 2
            self.cell_padding = 4
            self.cell_spacing = 1
            self.width = '100%'
            self.heading = None
            self.heading_align = 'center'
            self.heading_valign = 'middle'
            self.body = [['&nbsp;']*3]
            self.column1_align = 'left'
            self.cell_align = 'left'
            self.cell_line_breaks = 1
            self.colspan = None
            self.body_color= None
            self.heading_color=None
            # Now overlay the keyword arguments from caller
            for k in kw.keys():
                if self.__dict__.has_key(k):
                    self.__dict__[k] = kw[k]
                else:
                    print `k`, "isn't a valid parameter for this class."

        def __str__(self):
            """Generates the html for the entire table.
            """
            if self.tabletitle:
               s = [str(Name(self.tabletitle)) + '\n<P>']
            else:
               s = []

            s.append('<TABLE border=%s cellpadding=%s cellspacing=%s width="%s">\n' % \
                    (self.border, self.cell_padding, self.cell_spacing, self.width))
            if self.tabletitle:
                s.append('%s\n' % \
                        (self.caption_align, self.tabletitle))

            for i in range(len(self.body)):
                for j in range(len(self.body[i])):
                    if type(self.body[i][j]) == StringType:
                        #process cell contents to insert breaks for \n char.
                        if self.cell_line_breaks:
                            self.body[i][j] = string.replace(self.body[i][j], '\n','<br>')
                        else:
                            self.body[i][j] = Text(self.body[i][j])

            # Initialize colspan property to 1 for each
            # heading column if user doesn't provide it.
            if self.heading:
                if not self.colspan:
                    if type(self.heading[0]) == ListType:
                        self.colspan = [1]*len(self.heading[0])
                    else:
                        self.colspan = [1]*len(self.heading)
            # Construct heading spec
            #  can handle multi-row headings. colspan is a list specifying how many
            #  columns the i-th element should span. Spanning only applies to the first
            #  or only heading line.
            if self.heading:
                prefix = '<TR Align=' + self.heading_align + '> '
                postfix = '</TR>\n'
                middle = ''
                if type(self.heading[0]) == ListType:
                    for i in range(len(self.heading[0])):
                        middle = middle + '<TH ColSpan=%s%s>' % \
                                 (self.colspan[i], \
                                  self.get_body_color(self.heading_color,i)) \
                                  + str(self.heading[0][i]) +'</TH>'
                    s.append(prefix + middle + postfix)
                    for i in range(len(self.heading[1])):
                        middle = middle + '<TH>' + str(self.heading[i]) +'</TH>'
                    for heading_row in self.heading[1:]:
                        for i in range(len(self.heading[1])):
                            middle = middle + '<TH>' + heading_row[i] +'</TH>'
                        s.append(prefix + middle + postfix)
                else:
                    for i in range(len(self.heading)):
                        middle = middle + '<TH ColSpan=%s%s>' % \
                                 (self.colspan[i], \
                                  self.get_body_color(self.heading_color,i)) \
                                  + str(self.heading[i]) +'</TH>'
                    s.append(prefix + middle + postfix)
            # construct the rows themselves
            stmp = '<TD Align=%s %s>'
            for row in self.body:
                s.append('<TR>')
                for i in range(len(row)):
                    if i == 0 :
                        ss1 = self.column1_align
                    else:
                        ss1 = self.cell_align
                    s.append(stmp % (ss1, self.get_body_color(self.body_color,i)))
                    s.append(str(row[i]))
                    s.append('</TD>\n')
                s.append('</TR>\n')
            #close table
            s.append('</TABLE><P>\n')
            return string.join(s, '')

        def get_body_color(self, colors, i):
            """Return bgcolor argument for column number i
            """
            if colors is not None:
                try:
                    index = i % len(colors)
                    return ' bgcolor="%s"' % colors[index]
                except:
                    pass
            return ''

    #--------------------New stuff--------------------------#

    def _make_attr_inits(opts):
        """Construct a format string and dictionary suitable for value
        substitution of tag attributes.
        """
        a = []
        d = {}
        for name in opts:
            a.append('%('+name+')s')
            d[name] = ''
        return string.join(a, ''), d

    class AbstractTagSingle:
        "Abstract base class for all tag markup classes not requiring a closure tag."
        tagname = '' # to be provided by derived classes
        attrs = ()   # to be provided by derived classes
        attr_template = '' # to be provided by derived classes
        attr_dict = {}     # to be provided by derived classes

        def __init__(self, *args, **kw):
            self.__dict__['attr_dict'] = copy.copy(self.__class__.attr_dict)
            self.args = args
            for name, value in kw.items():
                name = string.lower(name)
                setattr(self, name, value)

        def __str__(self):
            """Generate an HTML formatted string for this object.
            """
            return  '<%s' % self.tagname + self.attr_template % self.attr_dict + '>'

        def __setattr__(self, name, value):
            """Intercept attribute assignments.

            If the attribute is a legal HTML tag attribute add it to the
            dict used for substitution in __str__, otherwise just set it as
            an instance attribute.
            """
            name = string.lower(name)
            if name in self.attrs:
                self.attr_dict[name] = ' %s="%s"' % (name, value)
            self.__dict__[name] = value

    class Image(AbstractTagSingle):
        """Inlined Image

        The *filename* argument is a filename, or URL of a graphic image,
        or a triple of ( filename, width, height ) where dimensions are in
        pixels. Where the filename is found to be a valid pathname to an
        existing graphic file that file will be read to determine its width and
        height properties. GIF, JPEG, and PNG files are understood.

        Keyword Arguments

            width  -- (int) Width in pixels
            height -- (int) Height in pixels
            border -- (int) Border width in pixels
            align  -- (string) 'top'|'middle'|'bottom'|'right'|'left'
            alt    -- (string) Text to substitute for the image in nonGUI browsers
            usemap -- Imagemap name or Map object
            ismap  -- Flag (1|0) indicating if a server side imagemap is available.
            absolute -- Absolute path to the directory containing the image
            prefix -- Relative path or URL to directory containing the image
            hspace -- Number of pixels to be added to the left and right of the image.
            vspace -- Number of pixels to be added to the top and bottom of the image.
            name -- A name for this image to be used by JavaScript
            Class -- A CSS class this tag belongs to.
            style -- A CSS inline style specification.
        """
        tagname = 'IMG'
        attrs = ('src', 'height', 'width', 'alt', 'border', 'align', 'class','id',
                 'hspace','vspace', 'lowsrc', 'name', 'style', 'usemap', 'ismap' )
        attr_template , attr_dict = _make_attr_inits(attrs)

        def __init__(self, *args, **kw):
            apply(AbstractTagSingle.__init__, (self,) + args, kw)
            self.prefix = None
            self.absolute = None
            if self.args:
                self.process_arg(self.args[0])

        def process_arg(self, arg):
            # unpack the tuple if needed
            if type(arg) == TupleType:
                self.filename = arg[0]
                self.width = arg[1]
                self.height = arg[2]
            else:
                self.filename = arg
            self.src = self.filename
            # if the file is there test it to get size
            if not self.attr_dict['width']: # assume if the user has set the width property
                # she knows the image size already or wants to resize it.
                try:
                    self.width, self.height = imgsize(self.filename)
                except IOError:
                    pass

        def calc_rel_path(self, from_dir=None):
            """Calculate the relative path from 'from_dir' to the
            absolute location of the image file.

            Sets self.prefix.
            """
            if not from_dir:
                from_dir = os.getcwd()
            if self.absolute:
                self.prefix = relpath(from_dir, self.absolute)

        def __str__(self):
            if self.prefix:
                self.src = os.path.join(self.prefix, self.filename)
            if not self.attr_dict['alt']:
                self.alt = os.path.basename(self.filename)
            if self.attr_dict['usemap']:
                if type(self.attr_dict['usemap']) == InstanceType:
                    # can use a Map instance for this
                    try:
                        self.usemap = '#' + self.usemap.name
                    except:
                        pass
            return AbstractTagSingle.__str__(self)

    IMG = Image # alias

    class BR(AbstractTagSingle):
        """Break tag. Argument is an integer integer multiplier. BR(2)=='<BR><BR>'
        """
        tagname = 'BR'
        attrs = ('clear',)
        attr_template , attr_dict = _make_attr_inits(attrs)

        def __str__(self):
            s = AbstractTagSingle.__str__(self)
            if self.args and type(self.args[0]) is IntType:
                return s*self.args[0]
            else:
                return s

    class Base(AbstractTagSingle):
        """Specify the base URL for all relative URLs in this document.

        One string argument required. It must be a complete file name, and
        is usually the original URL of this document.  If this file is
        moved, having the BASE set to the original URL eliminates the need
        to also move all the documents which are identified by relative
        URL links in this document.
        """
        tagname = 'BASE'
        attrs = ('href', 'target')
        attr_template , attr_dict = _make_attr_inits(attrs)

    class BaseFont(AbstractTagSingle):
        """Specify the font size for subsequent text.
        """
        tagname = 'BASEFONT'
        attrs = ('color', 'name', 'size')
        attr_template , attr_dict = _make_attr_inits(attrs)

    class Embed(AbstractTagSingle):
        """Embed an application in this document.
        """
        tagname = 'EMBED'
        attrs = ('align', 'border', 'height', 'hidden', 'hspace',
                 'name', 'palette', 'pluginspage', 'src', 'type',
                 'units', 'vspace', 'width')
        attr_template , attr_dict = _make_attr_inits(attrs)

    class HR(AbstractTagSingle):
        """Break the current text flow and insert a horizontal rule.
        """
        tagname = 'HR'
        attrs = ('align', 'class','id', 'color', 'noshade', 'size',
                 'style', 'width')
        attr_template , attr_dict = _make_attr_inits(attrs)

    class AbstractTag:
        "Abstract base class for all tag markup classes requiring a closure tag."
        tagname = '' # to be provided by derived classes
        attrs = ()   # to be provided by derived classes
        attr_template = '' # to be provided by derived classes
        attr_dict = {}      # to be provided by derived classes
        html_escape = 'ON'
        trailer = '\n'

        def __init__(self, *contents, **kw):
            self.__dict__['contents'] = []
            self.__dict__['attr_dict'] = copy.copy(self.__class__.attr_dict)
            for item in contents:
                self.contents.append(item)
            for name, value in kw.items():
                name = string.lower(name)
                setattr(self, name, value)

        def __str__(self):
            """Generate an HTML formatted string for this object.
            """
            s = ['<%s' % self.tagname]  # tag opening
            s.append(self.attr_template % self.attr_dict + '>') # options
            # crunch through the contents
            for item in self.contents:
                if type(item) is StringType and self.html_escape == 'ON':
                    s.append(escape(item))
                else:
                    s.append(str(item))
            # close out the marked region
            s.append( '</%s>' % self.tagname)
            return string.join(s, '') + self.trailer

        def __setattr__(self, name, value):
            """Intercept attribute assignments.

            If the attribute is a legal HTML tag attribute add it to the
            dict used for substitution in __str__, otherwise just set it as
            an instance attribute.
            """
            name = string.lower(name)
            if name in self.attrs:
                self.attr_dict[name] = ' %s="%s"' % (name, value)
            else:
                self.__dict__[name] = value

        def __call__(self, text):
            """Enable instances to be callable as text processing functions.

            For Example:

              >>> S = HTMLgen.Strong()
              >>> print S('Hi!')
              >>> Hi!
            """
            self.__dict__['contents'] = [text]
            return str(self)

        def __add__(self, other):
            """Support self + list
            """
            if type(other) is ListType:
                self.contents = self.contents + other
                return self
            else:
                raise TypeError, 'can only add lists to this object'

        def append(self, *items):
            """Append one or more items to the end of the container.
            """
            for item in items:
                self.contents.append(item)

        def prepend(self, *items):
            """Prepend one or more items to the top of the container.
            """
            for item in items:
                self.contents.insert(0, item)

        def empty(self):
            """Empty the contents of the container.
            """
            self.contents = []

        def __len__(self):
            """Return the integer length of the container list.
            """
            return len(self.contents)

        def last(self):
            """Return a reference to the last item in the container.
            """
            return self.contents[-1]

        def copy(self):
            """Return a full copy of the object.
            """
            return copy.deepcopy(self)

        def markup(self, rex=None, marker=None, **kw):
            """Markup the contained text matching a regular expression with
            a tag class instance or function.

            Arguments

                rex -- a regular expression object or pattern which will be used
                    to match all text patterns in the Paragraph body. Must have a single
                    group defined. Group 1 is the matching text that will be marked.
                    Default to all parenthetical text.
                marker -- an HTMLgen class instance to which the found text will
                    be sent for wrapping (using its __call__ method). Default is Emphasis.

            Keywords

                collapse -- When set to 1 removes the non-grouped matching text
                    from the output. Default 0.

            Returns the number of matching text groups.
            """
            collapse = 0
            if kw.has_key('collapse'): collapse = kw['collapse']
            text = string.join(map(str, self.contents))
            newtext, count = markup_re(text, rex, marker, collapse)
            if count:
                self.contents = [newtext]
                self.html_escape = 'OFF'
            return count

    class Area(AbstractTagSingle):
        """Specify a click-sensitive area of an image.

        The area is linked to a HREF specified by the *href* attribute.
        The *coords* attribute is required and describes the position of
        an area (in pixels) of the image in comma-separated x,y
        coordinates where the upper-left corner is "0,0". For shape='rect'
        (the default), it is "left,top,right,bottom". For shape='circle',
        it is "center_x,center_y,radius". For shape='polygon', it is
        successive x,y vertices of the polygon. If the first and last
        coordinates are not the same, then a segment is inferred to close
        the polygon. If no *href* keyword is given a *NOHREF* will be
        generated indicating that this region should generate no links.

        Keyword Arguments

            href --  Typically a reference to an image
            coords --  string holding a list of coordinates defining
            shape  -- 'rect'|'circle'|'polygon'
        """
        tagname = 'AREA'
        attrs = ('alt','class','coords','href','id','name',
    	     'onmouseout','onmouseover','shape','target')
        attr_template, attr_dict = _make_attr_inits(attrs)
        attr_dict['href'] = ' nohref'

    ###### FRAME SUPPORT ######

    class Frameset(AbstractTag):
        """Define a Frameset to contain Frames or more Framesets"""
        tagname = 'FRAMESET'
        attrs = ('border','bordercolor','cols','frameborder','framespacing','onblur',
    	     'onfocus','onload','onunload','rows')
        attr_template, attr_dict = _make_attr_inits(attrs)

    class NoFrames(AbstractTag):
        """Issue a message on browsers that don't support frames"""
        tagname = 'NOFRAMES'
        attrs = ()
        attr_template, attr_dict = _make_attr_inits(attrs)

        def __init__(self, *contents, **kw):
    	AbstractTag.__init__(self)
    	for content in contents: self.append(content)
    	for name, value in kw.items(): self.__setattr__(name,value)
    	if len(contents) == 0:
    	    self.append(Heading(2,'Frame ALERT!',align='center'),
    			Para("""This document is designed to be viewed using Netscape's
    			Frame features.  If you are seeing this message, you are using
    			a frame challenged browser."""),
    			Para('A ',Strong('Frame-capable'),' browser can be retrieved from',
    			     Href('http://home.netscape.com/','Netscape Communications'),
    			     ' or ',
    			     Href('http://www.microsoft.com/','Microsoft')))

    class Frame(AbstractTag):
        """Define the characteristics of an individual frame.

        Keywords Arguments

            src  -- is a HREF which points to the initial contents of the frame.
            name -- is the window name used by others to direct content into this frame.
            marginwidth -- is the number of pixels used to pad the left and right
                   sides of the frame.
            marginheight -- is the number of pixels used to pad the top and bottom
                   sides of the frame.
            scrolling -- is used to indicate scrolling policy set to 'yes'|'no'|'auto'
            noresize -- is a flag which instructs the browser to disallow frame resizing.
                   set to non zero lock size ( noresize=1 ).
        """

        tagname = 'FRAME'
        attrs = ('align','bordercolor','frameborder','marginheight','marginwidth','name',
    	     'noresize','scrolling','src')
        attr_template, attr_dict = _make_attr_inits(attrs)

    class Paragraph(AbstractTag):
        """Define a Paragraph.

        Takes a single string/object argument and the optional
        keyword argument 'align' which may be one of (left, right,
        center).  As always, Class and style keywords are supported.
        **Not to be confused with class P**. That is
        just for inserting a para break.

        Example:

            Paragraph('Some text to center', align='center')
        """
        tagname = 'P'
        attrs = ('class','id', 'style', 'align')
        attr_template , attr_dict = _make_attr_inits(attrs)

    Para = Paragraph # Alias

    # Headings

    class Heading(AbstractTag):
        """Heading markups for H1 - H6

        Heading(level, text, **kw)

        The *level* arg is an integer for the level of the heading.
        Valid levels are 1-6.
        The *text* arg is a string (or any object) for the text of the heading.
        Keyword arguments are align, Class, and style.

        For example:
        h = Heading(2, 'Chapter 3', align='center')
        """
        tagname = ''
        attrs = ('class','id', 'style', 'align')
        attr_template , attr_dict = _make_attr_inits(attrs)
        def __str__(self):
            if not self.tagname:
                if self.contents[0] not in (1,2,3,4,5,6):
                    raise AttributeError, "First arg of Heading must be int from 1 to 6."
                self.tagname = 'H%d' % self.contents[0]
                del self.contents[0]
            return AbstractTag.__str__(self)

    H = Head = Header = Heading # Aliases

    class Caption(AbstractTag):
        """Define a caption for a table.
        """
        tagname = 'CAPTION'
        attrs = ('class','id', 'style', 'align', 'valign')
        attr_template , attr_dict = _make_attr_inits(attrs)

    class TH(AbstractTag):
        """Define a table header cell.
        """
        tagname = 'TH'
        attrs = ('class','id', 'style', 'nowrap', 'align','valign','rowspan',
                 'colspan', 'height', 'width', 'bgcolor', 'background',
                 'bordercolor', 'bordercolordark', 'bordercolorlight')
        attr_template , attr_dict = _make_attr_inits(attrs)
        trailer = ''

    class TR(AbstractTag):
        """Define a row of cells within a table.
        """
        tagname = 'TR'
        attrs = ('class','id', 'style', 'align', 'bgcolor', 'bordercolor',
                 'bordercolordark', 'bordercolorlight', 'nowrap', 'valign')
        attr_template , attr_dict = _make_attr_inits(attrs)

    class TD(AbstractTag):
        """Define a table data cell.
        """
        tagname = 'TD'
        attrs = ('class','id', 'style', 'nowrap', 'align','valign', 'background',
                 'bordercolor', 'bordercolordark', 'bordercolorlight',
                 'rowspan','colspan','height', 'width','bgcolor')
        attr_template , attr_dict = _make_attr_inits(attrs)
        trailer = ''

    class TableLite(AbstractTag):
        """Container class for TH TD TR and Caption objects.
        """
        tagname = 'TABLE'
        attrs = ('class','id', 'style', 'align', 'background', 'border',
                 'bordercolor', 'bordercolordark', 'bordercolorlight',
                 'cols', 'frame', 'cellpadding', 'cellspacing',
                 'height', 'hspace', 'width', 'bgcolor', 'nowrap',
                 'rules', 'valign', 'vspace')
        attr_template , attr_dict = _make_attr_inits(attrs)

    class Pre(AbstractTag):
        """Render the text verbatim honoring line breaks and spacing.

        Does not escape special characters. To override this set html_escape
        to 'ON'.
        """
        tagname = 'PRE'
        attrs = ('width',)
        attr_template , attr_dict = _make_attr_inits(attrs)
        html_escape = 'OFF'

    class Strike(AbstractTag):
        """The text is struck trough with a horizontal line.
        """
        tagname = 'STRIKE'
        attrs = ('class','id', 'style')
        attr_template , attr_dict = _make_attr_inits(attrs)
        trailer = ''

    class Blockquote(AbstractTag):
        """Indent text as a block quotation.
        """
        tagname = 'BLOCKQUOTE'
        attrs = ('class','id', 'style')
        attr_template , attr_dict = _make_attr_inits(attrs)

    Indent = Blockquote

    class Big(AbstractTag):
        """Format text in a bigger font.
        """
        tagname = 'BIG'
        attrs = ('class','id', 'style')
        attr_template , attr_dict = _make_attr_inits(attrs)
        trailer = ''

    class Font(AbstractTag):
        """Set the size or color of the text.
        """
        tagname = 'FONT'
        attrs = ('color', 'face', 'size')
        attr_template , attr_dict = _make_attr_inits(attrs)
        trailer = ''

    class Address(AbstractTag):
        """A mailing address. Not a URL.
        """
        tagname = 'ADDRESS'
        attrs = ('class','id', 'style')
        attr_template , attr_dict = _make_attr_inits(attrs)
        trailer = ''

    class Emphasis(AbstractTag):
        """Format with additional emphasis. (usually italics)
        """
        tagname = 'EM'
        attrs = ('class','id', 'style')
        attr_template , attr_dict = _make_attr_inits(attrs)
        trailer = ''

    class Center(AbstractTag):
        """Center the text.
        """
        tagname = 'center'
        attrs = ()
        attr_template , attr_dict = _make_attr_inits(attrs)

    class Cite(AbstractTag):
        """A citation.
        """
        tagname = 'CITE'
        attrs = ('class','id', 'style')
        attr_template , attr_dict = _make_attr_inits(attrs)
        trailer = ''

    class KBD(AbstractTag):
        """Keyboard-like input.
        """
        tagname = 'KBD'
        attrs = ('class','id', 'style')
        attr_template , attr_dict = _make_attr_inits(attrs)
        html_escape = 'OFF'

    class Sample(AbstractTag):
        """Sample text. Escaping of special characters is not performed.

        To enable escaping set html_escape='ON'.
        """
        tagname = 'SAMP'
        attrs = ('class','id', 'style')
        attr_template , attr_dict = _make_attr_inits(attrs)
        html_escape = 'OFF'

    class Strong(AbstractTag):
        """Strongly emphasize the text.
        """
        tagname = 'STRONG'
        attrs = ('class','id', 'style')
        attr_template , attr_dict = _make_attr_inits(attrs)
        trailer = ''

    class Code(AbstractTag):
        """Code sample. Escaping of special characters is not performed.

        To enable escaping set html_escape='ON'.
        """
        tagname = 'CODE'
        attrs = ('class','id', 'style')
        attr_template , attr_dict = _make_attr_inits(attrs)
        html_escape = 'OFF'

    class Define(AbstractTag):
        """Format as definition text.
        """
        tagname = 'DFN'
        attrs = ('class','id', 'style')
        attr_template , attr_dict = _make_attr_inits(attrs)

    class Var(AbstractTag):
        """Used for variable names.
        """
        tagname = 'VAR'
        attrs = ('class','id', 'style')
        attr_template , attr_dict = _make_attr_inits(attrs)
        trailer = ''

    class Div(AbstractTag):
        """Specify a division within a document.
        """
        tagname = 'DIV'
        attrs = ('class','id', 'style', 'align', 'lang', 'nowrap')
        attr_template , attr_dict = _make_attr_inits(attrs)

    class TT(AbstractTag):
        """Format teletype style.
        """
        tagname = 'TT'
        attrs = ('class','id', 'style')
        attr_template , attr_dict = _make_attr_inits(attrs)
        trailer = ''

    class U(AbstractTag):
        """Underlined text.
        """
        tagname = 'U'
        attrs = ('class','id', 'style')
        attr_template , attr_dict = _make_attr_inits(attrs)
        trailer = ''

    class Nobr(AbstractTag):
        """Specify non-breaking text.
        """
        tagname = 'NOBR'
        attrs = ()
        attr_template , attr_dict = _make_attr_inits(attrs)
        trailer = ''

    class Small(AbstractTag):
        """Render in a smaller font.
        """
        tagname = 'SMALL'
        attrs = ('class','id', 'style')
        attr_template , attr_dict = _make_attr_inits(attrs)
        trailer = ''

    class Sub(AbstractTag):
        """Render as subscript.
        """
        tagname = 'SUB'
        attrs = ('class','id', 'style')
        attr_template , attr_dict = _make_attr_inits(attrs)
        trailer = ''

    class Sup(AbstractTag):
        """Render as subscript.
        """
        tagname = 'SUP'
        attrs = ('class','id', 'style')
        attr_template , attr_dict = _make_attr_inits(attrs)
        trailer = ''

    class Span(AbstractTag):
        """Generic tag to mark text for a style application.
        """
        tagname = 'SPAN'
        attrs = ('class','id', 'style')
        attr_template , attr_dict = _make_attr_inits(attrs)

    # Text Formatting Classes
    class InitialCaps:
        """Utility class to process text into Initial Upper Case style
        using Font specifications. All text is converted to upper case
        and the initial characters are altered by the size given by
        the optional second argument. The rest of the characters are
        altered by the size given in the optional third argument.

        For example:

           InitialCaps('We the people', '+3', '+1')
        """
        def __init__(self, text='', upsize = '+2', downsize = '+1'):
            self.hi = Font(size=upsize)
            self.lo = Font(size=downsize)
            self.text = text
            self.upsize = upsize
            self.downsize = downsize

        def __str__(self):
            list = string.split(self.text)
            wordlist = []
            for word in list:
                word = self.hi(string.upper(word[0])) + self.lo(string.upper(word[1:]))
                wordlist.append(word)
            return string.join(wordlist)

        def __call__(self, text):
            self.text = text
            return self.__str__()

    class Text:
        """Class to encapsulate text. Escape special characters for HTML.
        """
        def __init__(self, text=''):
            if type(text) == StringType:
                text = escape(text)
            self.text = str(text)

        def append(self, text=''):
            """Concatenate text characters onto the end.

            Will escape special characters.
            """
            if type(text) == StringType:
                text = escape(text)
            self.text = self.text + ' ' + str(text)

        def __str__(self):
            return self.text

    class RawText:
        """Class to encapsulate raw text. Does **NOT** escape special characters.
        """
        def __init__(self, text=''):
            self.text = text

        def append(self, text):
            self.text = self.text + str(text)

        def __str__(self):
            return self.text

    # ALIASES
    PRE = Pre
    Bold = STRONG = Strong
    Italic = EM = Emphasis
    Typewriter = TT

    class Comment:
        """Place a comment internal to the HTML document.

        Will not be visible from the browser.
        """
        def __init__(self, text=''):
            self.text = text

        def __str__(self):
            return '\n<!-- %s -->\n' % self.text

        def __call__(self, text):
            self.text = text
            return self.__str__()

    ###### UTILITIES USED INTERNALLY ########

    def escape(text, replace=string.replace):
        """Converts the special characters '<', '>', and '&'.

        RFC 1866 specifies that these characters be represented
        in HTML as < > and & respectively. In Python
        1.5 we use the new string.replace() function for speed.
        """
        text = replace(text, '&', '&amp;') # must be done 1st
        text = replace(text, '<', '&lt;')
        text = replace(text, '>', '&gt;')
        return text

    def markup_re(text, rex=None, marker=None, collapse=0):
        """Markup the contained text with a given re pattern/object with
        a given tag class instance. Uses re module.

        Arguments

            text -- string to act on
            rex -- a regular expression object or pattern from the re module which will be used
                to match all text patterns in the Paragraph body. Must have a single
                group defined. Group 1 is the matching text that will be marked.
                Defaults to all parenthetical text.
            marker -- an HTMLgen class instance to which the found text will
                be sent for wrapping (using its __call__ method). Default is Emphasis.
                Can be your function as well.
            collapse -- Optional flag. When set to 1 removes the non-
                grouped matching text from the output. Default 0.

        Returns tuple pair of the marked text and the number of matching text groups.
        """
        if rex is None: rex = re.compile('\(([^)]*)\)')
        if marker is None: marker = Emphasis()
        if type(rex) == StringType: rex = re.compile(rex)
        endpoints = []
        output = []
        i = 0
        count = 0
        while 1:
            # build up a list of tuples: ( 'u'|'m', begin, end )
            # 'u' indicates unmarked text and 'm' marked text
            # begin and end is the range of characters
            match = rex.search(text, i)
            if match:
                if collapse: #skip chars outside group1
                    endpoints.append( ('u', i, match.start(0)) )
                    i = match.end(0)
                else: #incl chars outside group1
                    endpoints.append( ('u', i, match.start(1)) )
                    i = match.end(1)
                endpoints.append( ('m', match.start(1), match.end(1)) ) #text2Bmarked
                count = count + 1
            else:
                endpoints.append( ('u', i, len(text) ) ) # tack on an ending slice
                break

        if count == 0: return text, 0  # didn't find any matches
        for (style, begin, end) in endpoints:
            if style == 'm':
                output.append(marker(text[begin:end]))
            else:
                output.append(text[begin:end])
        return string.join(output, ''), count

    class URL:
        """Represent a Universal Resource Locator.

        Assumed to be of the form: **http://www.node.edu/directory/file.html**
        with *http* being an example protocol, *www.node.edu* being an example
        network node, *directory* being the directory path on that node, and
        *file.html* being the target filename. The argument string is parsed
        into attributes .proto , .node , .dir , .file respectively and may
        be altered individually after instantiation. The __str__ method
        simply reassembles the components into a full URL string.
        """
        def __init__(self, url):
            self.url = url
            self.parse(url)
        def parse(self, url):
            import urlparse
            self.unparse = urlparse.urlunparse
            self.proto, self.node, self.path, self.params, self.query, self.fragment = \
                        urlparse(url)
            self.dir, self.file = self.split(self.path)

        def split(self, p):
            """Same as posixpath.split()

            Copied here for availability on the Mac.
            """
            i = string.rfind(p, '/') + 1
            head, tail = p[:i], p[i:]
            if head and head != '/'*len(head):
                    while head[-1] == '/':
                            head = head[:-1]
            return head, tail

        def __str__(self):
            return self.unparse( (self.proto,
                                  self.node,
                                  self.dir+self.file,
                                  self.params,
                                  self.query, self.fragment) )

        def copy(self):
            """No argument. Return a copy of this object.
            """
            return copy.deepcopy(self)

    def mpath(path):
        """Converts a POSIX path to an equivalent Macintosh path.

        Works for ./x ../x /x and bare pathnames.
        Won't work for '../../style/paths'.

        Also will expand environment variables and Cshell tilde
        notation if running on a POSIX platform.
        """
        import os
        if os.name == 'mac' : #I'm on a Mac
            if path[:3] == '../': #parent
                mp = '::'
                path = path[3:]
            elif path[:2] == './': #relative
                mp = ':'
                path = path[2:]
            elif path[0] == '/': #absolute
                mp = ''
                path = path[1:]
            else: # bare relative
                mp = ''
            pl = string.split(path, '/')
            mp = mp + string.join(pl, ':')
            return mp
        elif os.name == 'posix': # Expand Unix variables
            if path[0] == '~' :
                path = os.path.expanduser( path )
            if '$' in path:
                path = os.path.expandvars( path )
            return path
        else: # needs to take care of dos & nt someday
            return path

    #_realopen = open  #If I do a lot of mpath I can overload 'open'
    #def open(filename, mode = 'r', bufsize = -1):
    #    return _realopen( mpath(filename), mode, bufsize )

    def relpath(path1, path2):
        """Return the relative path from directory 'path1' to directory 'path2'

        Both arguments are assumed to be directory names as there is no
        way to really distinguish a file from a directory by names
        alone. To loosen this restriction one can either assume that both
        arguments represent files or directories currently extant so that
        they can be tested, or add extra arguments to flag the path types
        (file or directory).

        I chose to impose this restriction because I will use this function
        in places where the pathnames are for files yet to be created.
        """
        common = os.path.commonprefix([path1, path2])
        sliceoff = len(common)
        path1 = path1[sliceoff:]
        path2 = path2[sliceoff:]

        dirs1 = string.split(path1, os.sep) # list of directory components below
                                            # the common path
        dirs1 = filter(lambda x: x, dirs1)  # filter out empty elements
        rel = (os.pardir+os.sep)*len(dirs1) # construct the relative path to the
                                            # common point
        return rel+path2

    def compare_f2f(f1, f2):
        """Helper to compare two files, return 0 if they are equal."""

        BUFSIZE = 8192
        fp1 = open(f1)
        try:
            fp2 = open(f2)
            try:
                while 1:
                    b1 = fp1.read(BUFSIZE)
                    b2 = fp2.read(BUFSIZE)
                    if not b1 and not b2: return 0
                    c = cmp(b1, b2)
                    if c:
                        return c
            finally:
                fp2.close()
        finally:
            fp1.close()

    def compare_s2f(s, f2):
        """Helper to compare a string to a file, return 0 if they are equal."""

        BUFSIZE = 8192
        i = 0
        fp2 = open(f2)
        try:
            while 1:
                try:
                    b1 = s[i: i + BUFSIZE]
                    i = i + BUFSIZE
                except IndexError:
                    b1 = ''
                b2 = fp2.read(BUFSIZE)
                if not b1 and not b2: return 0
                c = cmp(b1, b2)
                if c: return c
        finally:
            fp2.close()