__add__ ( self,  other )

returns an Expression to match this Expression then the other one

__or__ ( self,  other )

returns an Expression matching this Expression or (if that fails) the other one

__str__ ( self )

the corresponding pattern string

_find_groups ( self,  tag )

return a list of all groups matching the given tag

_modify_leaves ( self,  func )

internal function for manipulating the leaves of an expression

This really needs to be some sort of visit pattern, but I'm not sure the best way to do it. THIS METHOD MAY CHANGE.

_select_names ( self,  names )

internal function used by select_names.

Don't call this function. Will likely be removed in future versions.

copy ( self )

do a deep copy on this Expression tree

features ( self )

return a list of all features

group_names ( self )

the list of group names used by this Expression and its children

make_iterator (
        self,
        tag="record",
        debug_level=0,
        )

create an iterator for this regexp; the tag defines a record

make_parser ( self,  debug_level=0 )

create a SAX compliant parser for this regexp