22 Oct
2009
22 Oct
'09
7:29 a.m.
Hi, On Thursday 22 October 2009 09:47:32 Martijn van Steenbergen wrote:
Bonjour café,
data ExprF r = Add r r
| Sub r r | Mul r r | Div r r | Num Int
This is a well-known pattern that for example allows nice notation of morphisms. But what is it called? ...
The multirec package calls this the "pattern functor" (more accurately, it generates a sum-of-products-like higher order functor whose fixed point is isomorphic to your family of types, and calls that the pattern functor). -- Greetings, Daniel