PlasmaCalcs.tools.properties.dict_with_defaults_property

PlasmaCalcs.tools.properties.dict_with_defaults_property(internal_name, *, key_aliases, doc=None)

return a property which gives a dictionary, and gives key_aliases a chance to edit the dict.

internal_name: str

the name where this property is stored internally for obj.

key_aliases: str or iterable of strs.

the attributes of obj which are alias_key_of this property.

str –> use obj.key_aliases.

doc: None or str

the docstring for this property

if None, use f’dict with defaults determined by self.{key_aliases}’.

Example:

class Foo():

special = dict_with_defaults_property(‘_special’, key_aliases=’_special_key_aliases’)

_special_key_aliases = [‘special_key1’, ‘special_key2’]

special_key1 = alias_key_of(‘_special’, ‘key1’, setdefault_value=5)

special_key2 = alias_key_of(‘_special’, ‘key2’)

foo = Foo()

# every time getting the dict from foo, use all the setdefault values as appropriate:

foo.special # –> dict(key1=5)

foo.special = dict(key1=100)

foo.special # –> dict(key1=100)

foo.special = dict(key3=30)

foo.special # –> dict(key3=30, key1=5)

foo.special_key1 = 70

foo.special # –> dict(key3=30, key1=70)

del foo.special[‘key1’]

foo.special # –> dict(key3=30, key1=5) # key1 was missing, so its setdefault value is used.

# note that the dict itself is a normal dict; the magic happens when doing foo.special:

foo.special = dict(key3=10, key1=80)

special = foo.special

special # –> dict(key3=10, key1=80)

del special[‘key1’]

special # –> dict(key3=10)

foo.special # –> dict(key3=10, key1=5) # key1 was missing, so its setdefault value is used.

special # –> dict(key3=10, key1=5) # a new dict isn’t created; foo.special is special.