Namespace

Namespace.

A namespace is nothing more than a dictionary with some benefits:

• items use item.name as dictionary key. This is checked.
• items cannot be overwritten
• items cannot be deleted
• the namespace can be locked for modifications via lock.
• iteration over the namespaces yields the items and not their keys.

Namespace Examples

Examples.

>>> from collections import namedtuple
>>> NamedObject = namedtuple('NamedObject', 'name foo bar')
>>> namespace = Namespace([NamedObject('a', 1, 2)])
>>> namespace.add(NamedObject('b', 3, 4))
>>> namespace['c'] = NamedObject('c', 5, 6)
>>> namespace.is_locked
False
>>> for item in namespace:
...     item
NamedObject(name='a', foo=1, bar=2)
NamedObject(name='b', foo=3, bar=4)
NamedObject(name='c', foo=5, bar=6)
>>> for item in namespace.keys():
...     item
'a'
'b'
'c'
>>> for item in namespace.values():
...     item
NamedObject(name='a', foo=1, bar=2)
NamedObject(name='b', foo=3, bar=4)
NamedObject(name='c', foo=5, bar=6)
>>> namespace['b']
NamedObject(name='b', foo=3, bar=4)
>>> namespace['d']
Traceback (most recent call last):
...
KeyError: 'd'
>>> namespace.get_dym('d')
Traceback (most recent call last):
...
ValueError: 'd'. Known are 'a', 'b' and 'c'.

Locking:

>>> namespace.lock()
>>> namespace.is_locked
True
>>> namespace['d'] = NamedObject('d', 7, 8)
Traceback (most recent call last):
...
ucdp.exceptions.LockError: Namespace is already locked. Cannot add items anymore.

>>> len(namespace)
3

Namespace

Bases: dict

Namespace.

is_locked property

is_locked

Locked.

lock

lock()

Lock.

add

add(item, exist_ok=False)

Add.

get_dym

get_dym(name)

Get NamedObject.

pop

pop(*args)

Pop value.

If key is in the dictionary, remove it and return its value, else return default. If default is not given and key is not in the dictionary, a KeyError is raised.

This operation is forbidden.

popitem

popitem()

Remove and return a (key, value) pair from the dictionary.

This operation is forbidden.

set_default

set_default(key, value=None)

Set Default.

If key is in the dictionary, return its value. If not, insert key with a value of default and return default. default defaults to None.

update

update(other)

Update the dictionary with the key/value pairs from other.