diff options
Diffstat (limited to 'libbe/properties.py')
| -rw-r--r-- | libbe/properties.py | 10 |
1 files changed, 6 insertions, 4 deletions
diff --git a/libbe/properties.py b/libbe/properties.py index 176e898..a8e89fb 100644 --- a/libbe/properties.py +++ b/libbe/properties.py @@ -28,6 +28,7 @@ for more information on decorators. import unittest + class ValueCheckError (ValueError): def __init__(self, name, value, allowed): msg = "%s not in %s for %s" % (value, allowed, name) @@ -65,10 +66,11 @@ def doc_property(doc=None): return funcs return decorator -def local_property(name): +def local_property(name, null=None): """ Define get/set access to per-parent-instance local storage. Uses ._<name>_value to store the value for a particular owner instance. + If the ._<name>_value attribute does not exist, returns null. """ def decorator(funcs): if hasattr(funcs, "__call__"): @@ -78,7 +80,7 @@ def local_property(name): def _fget(self): if fget is not None: fget(self) - value = getattr(self, "_%s_value" % name, None) + value = getattr(self, "_%s_value" % name, null) return value def _fset(self, value): setattr(self, "_%s_value" % name, value) @@ -90,7 +92,7 @@ def local_property(name): return funcs return decorator -def settings_property(name): +def settings_property(name, null=None): """ Similar to local_property, except where local_property stores the value in instance._<name>_value, settings_property stores the @@ -104,7 +106,7 @@ def settings_property(name): def _fget(self): if fget is not None: fget(self) - value = self.settings.get(name, None) + value = self.settings.get(name, null) return value def _fset(self, value): self.settings[name] = value |