|category-extras-0.53.6: Various modules and constructs inspired by category theory||Contents||Index|
|Portability||non-portable (either class-associated types or MPTCs with fundeps)|
|Maintainer||Edward Kmett <firstname.lastname@example.org>|
|This module declares the HasTerminalObject and HasInitialObject classes.
These are defined in terms of class-associated types rather than functional dependencies
because most of the time when you are manipulating a category you don't care about them;
this gets them out of the signature of most functions that use the category.
Both of these are special cases of the idea of a (co)limit.
|class Category k => HasTerminalObject k t | k -> t where|
|The Category k has a terminal object Terminal k such that for all objects a in k,
there exists a unique morphism from a to Terminal k.
|class Category k => HasInitialObject k i | k -> i where|
|The Category k has an initial (coterminal) object Initial k such that for all objects
a in k, there exists a unique morphism from Initial k to a.
|Produced by Haddock version 2.1.0|