Documentation for the new range type support.pr/5

1 files changed, 13 insertions, 0 deletions

diff --git a/lib/sqlalchemy/dialects/postgresql/ranges.py b/lib/sqlalchemy/dialects/postgresql/ranges.py
index 2054ef137..e7ab1d5b5 100644
--- a/lib/sqlalchemy/dialects/postgresql/ranges.py
+++ b/lib/sqlalchemy/dialects/postgresql/ranges.py
@@ -9,6 +9,19 @@ from ... import types as sqltypes
 __all__ = ('INT4RANGE', 'INT8RANGE', 'NUMRANGE')
 
 class RangeOperators(object):
+    """
+    This mixin provides functionality for the Range Operators
+    listed in Table 9-44 of the `postgres documentation`__ for Range
+    Functions and Operators. It is used by all the range types
+    provided in the ``postgres`` dialect and can likely be used for
+    any range types you create yourself.
+
+    __ http://www.postgresql.org/docs/devel/static/functions-range.html
+
+    No extra support is provided for the Range Functions listed in
+    Table 9-45 of the postgres documentation. For these, the normal
+    :func:`~sqlalchemy.sql.expression.func` object should be used.
+    """
 
     class comparator_factory(sqltypes.Concatenable.Comparator):
         """Define comparison operations for range types."""