From b22edf1d8a16467a8d5625f4ddf7dca9403bdfe0 Mon Sep 17 00:00:00 2001 From: Mike Bayer Date: Thu, 11 Dec 2008 23:28:01 +0000 Subject: - turn __visit_name__ into an explicit member. [ticket:1244] --- lib/sqlalchemy/sql/visitors.py | 21 +++++++++++---------- 1 file changed, 11 insertions(+), 10 deletions(-) (limited to 'lib/sqlalchemy/sql/visitors.py') diff --git a/lib/sqlalchemy/sql/visitors.py b/lib/sqlalchemy/sql/visitors.py index 5d1d53cf8..17b9c59d5 100644 --- a/lib/sqlalchemy/sql/visitors.py +++ b/lib/sqlalchemy/sql/visitors.py @@ -28,21 +28,22 @@ __all__ = ['VisitableType', 'Visitable', 'ClauseVisitor', 'cloned_traverse', 'replacement_traverse'] class VisitableType(type): - """Metaclass which applies a `__visit_name__` attribute and - `_compiler_dispatch` method to classes. + """Metaclass which checks for a `__visit_name__` attribute and + applies `_compiler_dispatch` method to classes. """ - def __init__(cls, clsname, bases, dict): - if not '__visit_name__' in cls.__dict__: - m = re.match(r'_?(\w+?)(?:Expression|Clause|Element|$)', clsname) - x = m.group(1) - x = re.sub(r'(?!^)[A-Z]', lambda m:'_'+m.group(0).lower(), x) - cls.__visit_name__ = x.lower() + def __init__(cls, clsname, bases, clsdict): + if cls.__name__ == 'Visitable': + super(VisitableType, cls).__init__(clsname, bases, clsdict) + return + + assert hasattr(cls, '__visit_name__'), "`Visitable` descendants " \ + "should define `__visit_name__`" # set up an optimized visit dispatch function # for use by the compiler - visit_name = cls.__dict__["__visit_name__"] + visit_name = cls.__visit_name__ if isinstance(visit_name, str): getter = operator.attrgetter("visit_%s" % visit_name) def _compiler_dispatch(self, visitor, **kw): @@ -53,7 +54,7 @@ class VisitableType(type): cls._compiler_dispatch = _compiler_dispatch - super(VisitableType, cls).__init__(clsname, bases, dict) + super(VisitableType, cls).__init__(clsname, bases, clsdict) class Visitable(object): """Base class for visitable objects, applies the -- cgit v1.2.1