diff options
Diffstat (limited to 'docs/ref')
| -rw-r--r-- | docs/ref/models/fields.txt | 14 |
1 files changed, 7 insertions, 7 deletions
diff --git a/docs/ref/models/fields.txt b/docs/ref/models/fields.txt index eb93bbab6e..4b962f30c0 100644 --- a/docs/ref/models/fields.txt +++ b/docs/ref/models/fields.txt @@ -207,20 +207,20 @@ support tablespaces for indexes, this option is ignored. The default value for the field. This can be a value or a callable object. If callable it will be called every time a new object is created. -The default cannot be a mutable object (model instance, list, set, etc.), as a -reference to the same instance of that object would be used as the default +The default can't be a mutable object (model instance, ``list``, ``set``, etc.), +as a reference to the same instance of that object would be used as the default value in all new model instances. Instead, wrap the desired default in a -callable. For example, if you had a custom ``JSONField`` and wanted to specify -a dictionary as the default, use a function as follows:: +callable. For example, if you want to specify a default ``dict`` for +:class:`~django.contrib.postgres.fields.JSONField`, use a function:: def contact_default(): return {"email": "to1@example.com"} contact_info = JSONField("ContactInfo", default=contact_default) -Note that ``lambda``\s cannot be used for field options like ``default`` -because they cannot be :ref:`serialized by migrations <migration-serializing>`. -See that documentation for other caveats. +``lambda``\s can't be used for field options like ``default`` because they +can't be :ref:`serialized by migrations <migration-serializing>`. See that +documentation for other caveats. For fields like :class:`ForeignKey` that map to model instances, defaults should be the value of the field they reference (``pk`` unless |