fails:The defined? keyword for an expression with logical connectives returns nil for an expression with '!' and an unset class variable
fails:The defined? keyword for an expression with logical connectives returns nil for an expression with 'not' and an unset class variable
fails:The defined? keyword for a variable scoped constant returns nil if the scoped constant is not defined
fails:The defined? keyword for a variable scoped constant returns 'constant' if the constant is defined in the scope of the variable reference
fails:The defined? keyword for a variable scoped constant returns nil if the class scoped constant is not defined
fails:The defined? keyword for a variable scoped constant returns 'constant' if the constant is defined in the scope of the class variable
