Darryl Luff wrote:
> [...] I created get/set methods for each field to avoid
> problems if I mis-type the dictionary keys.
An automated way to do that:
class M(type):
def create_properties(cls, obj, *prop_names, **prop_names_values):
for pname in prop_names:
setattr(cls, pname, cls._create_property(pname))
for pname, value in prop_names_values.iteritems():
setattr(cls, pname, cls._create_property(pname, value))
def _create_property(cls, pname, init_value = None):
container_name = '__' + pname
def setter(self, value): setattr(self, container_name, value)
def getter(self):
if not hasattr(self, container_name):
return init_value
return getattr(self, container_name)
return property(getter, setter)
class A(object):
__metaclass__ = M
def __init__(self):
A.create_properties(self, 'prop1', 'prop2', prop3=8, **{'prop4':9})
a = A()
print a.prop1
a.prop1 = 3
print a.prop1
print a.prop3
a.prop3 = 'asdf'
print a.prop3
print a.prop4
> Now I have a couple of questions:
> - What is the recommended 'python' way to implement this class? and
Don't know.
> - If what I'm doing is OK, is there an easy way to load a dictionary
> from the string representation without parsing the string manually?
I wouldn't write the dictionary directly to a file, I would use ConfigParser.
An easy but terribly insecure way to do what you ask is using eval (for ex.:
eval(`{ 1:1 }`) ) but I do not recommend this.
Javier
PS: M was my first metaclass! :) If the same result can be achieved without one
I would like to know the way.
_______________________________________________
Tutor maillist - Tutor@python.org
http://mail.python.org/mailman/listinfo/tutor
