- build out a new base type for Array, as well as new any/all operators

- any/all work for Array as well as subqueries, accepted by MySQL
- Postgresql ARRAY now subclasses Array
- fixes #3516

1 files changed, 11 insertions, 1 deletions

diff --git a/lib/sqlalchemy/sql/functions.py b/lib/sqlalchemy/sql/functions.py
index 538a2c549..80ee31b0f 100644
--- a/lib/sqlalchemy/sql/functions.py
+++ b/lib/sqlalchemy/sql/functions.py
@@ -12,7 +12,7 @@ from . import sqltypes, schema
 from .base import Executable, ColumnCollection
 from .elements import ClauseList, Cast, Extract, _literal_as_binds, \
     literal_column, _type_from_args, ColumnElement, _clone,\
-    Over, BindParameter, FunctionFilter
+    Over, BindParameter, FunctionFilter, Grouping
 from .selectable import FromClause, Select, Alias
 
 from . import operators
@@ -233,6 +233,16 @@ class FunctionElement(Executable, ColumnElement, FromClause):
         return BindParameter(None, obj, _compared_to_operator=operator,
                              _compared_to_type=self.type, unique=True)
 
+    def self_group(self, against=None):
+        # for the moment, we are parenthesizing all array-returning
+        # expressions against getitem.  This may need to be made
+        # more portable if in the future we support other DBs
+        # besides postgresql.
+        if against is operators.getitem:
+            return Grouping(self)
+        else:
+            return super(FunctionElement, self).self_group(against=against)
+
 
 class _FunctionGenerator(object):
     """Generate :class:`.Function` objects based on getattr calls."""