Opened 7 years ago

#27 new defect

Eq instance is not compatible with Monoid instance for Picture

Reported by: cdsmith Owned by:
Priority: normal Milestone:
Component: Unknown Version: 1.5.0
Keywords: Cc:

Description

The Monoid instance for Picture obeys neither the identity nor associativity laws when equality is determined by the Eq instance. This could be fixed by either: (a) adding special cases for Blank and Pictures as top-level constructors in the Monoid instance, or (b) flattening the nesting structure implicitly during comparison in the Eq instance.

Change History (0)

Note: See TracTickets for help on using tickets.