diff options
Diffstat (limited to 'lib/sqlalchemy/sql/expression.py')
| -rw-r--r-- | lib/sqlalchemy/sql/expression.py | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/lib/sqlalchemy/sql/expression.py b/lib/sqlalchemy/sql/expression.py index 96147a94a..8a92dba0d 100644 --- a/lib/sqlalchemy/sql/expression.py +++ b/lib/sqlalchemy/sql/expression.py @@ -1035,6 +1035,14 @@ def _no_literals(element): else: return element +def _only_column_elements(element): + if hasattr(element, '__clause_element__'): + element = element.__clause_element__() + if not isinstance(element, ColumnElement): + raise exc.ArgumentError("Column-based expression object expected; " + "got: %r" % element) + return element + def _corresponding_column_or_error(fromclause, column, require_embedded=False): c = fromclause.corresponding_column(column, require_embedded=require_embedded) |