diff options
Diffstat (limited to 'lib/sqlalchemy/sql/visitors.py')
| -rw-r--r-- | lib/sqlalchemy/sql/visitors.py | 35 |
1 files changed, 17 insertions, 18 deletions
diff --git a/lib/sqlalchemy/sql/visitors.py b/lib/sqlalchemy/sql/visitors.py index 27499b5f7..43b7cb4af 100644 --- a/lib/sqlalchemy/sql/visitors.py +++ b/lib/sqlalchemy/sql/visitors.py @@ -24,6 +24,7 @@ http://techspot.zzzeek.org/2008/01/23/expression-transformations/ . """ from collections import deque +import operator from .. import exc from .. import util @@ -63,26 +64,24 @@ def _generate_compiler_dispatch(cls): % cls.__name__ ) - code = ( - "def _compiler_dispatch(self, visitor, **kw):\n" - " try:\n" - " meth = visitor.visit_%(name)s\n" - " except AttributeError as err:\n" - " util.raise_(\n" - " exc.UnsupportedCompilationError(visitor, cls), \n" - " replace_context=err)\n" - " else:\n" - " return meth(self, **kw)\n" - ) % {"name": visit_name} - - _compiler_dispatch = langhelpers._exec_code_in_env( - code, {"exc": exc, "cls": cls, "util": util}, "_compiler_dispatch" - ) + name = "visit_%s" % visit_name + getter = operator.attrgetter(name) + + def _compiler_dispatch(self, visitor, **kw): + """Look for an attribute named "visit_<visit_name>" on the + visitor, and call it with the same kw params. - _compiler_dispatch.__doc__ = """Look for an attribute named "visit_" - + self.__visit_name__ on the visitor, and call it with the same - kw params. """ + try: + meth = getter(visitor) + except AttributeError as err: + util.raise_( + exc.UnsupportedCompilationError(visitor, cls), + replace_context=err, + ) + else: + return meth(self, **kw) + cls._compiler_dispatch = ( cls._original_compiler_dispatch ) = _compiler_dispatch |