Package Martel :: Module Expression :: Class NullOp
[show private | hide private]
[frames | no frames]

Class NullOp

Expression --+
             |
            NullOp


Method Summary
  __init__(self)
() Doesn't match anything.
  __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
  copy(self)
do a deep copy on this Expression tree
    Inherited from Expression
  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, debug_level)
create an iterator for this regexp; the 'tag' defines a record
  make_parser(self, debug_level)
create a SAX compliant parser for this regexp

Method Details

__init__(self)
(Constructor)

()

Doesn't match anything.  This is a null operation.  It's
useful if you want a valid initial object from which to build,
as in:

  exp = NullOp()
  for c in string.split(line):
    exp = exp + Str(c)

(That's contrived -- see Time.py for a real use.)

__add__(self, other)
(Addition operator)

returns an Expression to match this Expression then the other one
Overrides:
Martel.Expression.Expression.__add__ (inherited documentation)

__or__(self, other)
(Or operator)

returns an Expression matching this Expression or (if that fails) the other one
Overrides:
Martel.Expression.Expression.__or__ (inherited documentation)

__str__(self)
(Informal representation operator)

the corresponding pattern string
Overrides:
Martel.Expression.Expression.__str__ (inherited documentation)

copy(self)

do a deep copy on this Expression tree
Overrides:
Martel.Expression.Expression.copy (inherited documentation)

Generated by Epydoc 2.1 on Sat Jul 16 15:48:59 2005 http://epydoc.sf.net