Id#

class discopy.cat.Id(dom)[source]#

Bases: Arrow

Defines the identity arrow on dom, i.e. with an empty list of boxes.

Parameters:

dom (cat.Ob) – Any object.

Examples

>>> x = Ob('x')
>>> assert Id(x) == Arrow(x, x, [])
classmethod from_tree(tree)#

Decodes a tree as an arrow.