diff options
Diffstat (limited to 'lib/sqlalchemy/sql.py')
| -rw-r--r-- | lib/sqlalchemy/sql.py | 25 |
1 files changed, 18 insertions, 7 deletions
diff --git a/lib/sqlalchemy/sql.py b/lib/sqlalchemy/sql.py index 0cacea12d..d978ee208 100644 --- a/lib/sqlalchemy/sql.py +++ b/lib/sqlalchemy/sql.py @@ -153,12 +153,9 @@ def cast(clause, totype, **kwargs): or cast(table.c.timestamp, DATE) """ - # handle non-column clauses (e.g. cast(1234, TEXT) - if not hasattr(clause, 'label'): - clause = literal(clause) - totype = sqltypes.to_instance(totype) - return Function('CAST', CompoundClause("AS", clause, TypeClause(totype)), type=totype, **kwargs) - + return Cast(clause, totype, **kwargs) + + def exists(*args, **params): params['correlate'] = True s = select(*args, **params) @@ -320,6 +317,7 @@ class ClauseVisitor(object): def visit_clauselist(self, list):pass def visit_calculatedclause(self, calcclause):pass def visit_function(self, func):pass + def visit_cast(self, cast):pass def visit_label(self, label):pass def visit_typeclause(self, typeclause):pass @@ -974,7 +972,20 @@ class Function(CalculatedClause): c.accept_visitor(visitor) visitor.visit_function(self) - +class Cast(ColumnElement): + def __init__(self, clause, totype, **kwargs): + if not hasattr(clause, 'label'): + clause = literal(clause) + self.type = sqltypes.to_instance(totype) + self.clause = clause + self.typeclause = TypeClause(self.type) + def accept_visitor(self, visitor): + self.clause.accept_visitor(visitor) + self.typeclause.accept_visitor(visitor) + visitor.visit_cast(self) + def _get_from_objects(self): + return self.clause._get_from_objects() + class FunctionGenerator(object): """generates Function objects based on getattr calls""" def __init__(self, engine=None): |