diff options
Diffstat (limited to 'lib/sqlalchemy/sql/operators.py')
| -rw-r--r-- | lib/sqlalchemy/sql/operators.py | 12 |
1 files changed, 10 insertions, 2 deletions
diff --git a/lib/sqlalchemy/sql/operators.py b/lib/sqlalchemy/sql/operators.py index 17a9d3086..a2778c7c4 100644 --- a/lib/sqlalchemy/sql/operators.py +++ b/lib/sqlalchemy/sql/operators.py @@ -214,10 +214,13 @@ class custom_op(object): """ __name__ = 'custom_op' - def __init__(self, opstring, precedence=0, is_comparison=False): + def __init__( + self, opstring, precedence=0, is_comparison=False, + natural_self_precedent=False): self.opstring = opstring self.precedence = precedence self.is_comparison = is_comparison + self.natural_self_precedent = natural_self_precedent def __eq__(self, other): return isinstance(other, custom_op) and \ @@ -826,6 +829,11 @@ def is_ordering_modifier(op): return op in (asc_op, desc_op, nullsfirst_op, nullslast_op) + +def is_natural_self_precedent(op): + return op in _natural_self_precedent or \ + isinstance(op, custom_op) and op.natural_self_precedent + _associative = _commutative.union([concat_op, and_, or_]) _natural_self_precedent = _associative.union([getitem]) @@ -893,7 +901,7 @@ _PRECEDENCE = { def is_precedent(operator, against): - if operator is against and operator in _natural_self_precedent: + if operator is against and is_natural_self_precedent(operator): return False else: return (_PRECEDENCE.get(operator, |