标签：bsp com list table res cat compose ann with
We annihilate the need for the ol‘ nested for loop using Applicatives.
For example we have this kind of nested loop code:
for(x in xs){ for(x in ys){ for(z in zs){ } } }
We can refactor it by using List comprehension:
const {List} = Immutable;
const res1 = List.of(x => x).ap(List([1,2,3])); console.log(res1) // List [ 1,2,3 ]
const res1 = List.of(x => y=> `${x} - ${y}`) .ap(List([‘teeshirt‘, ‘sweater‘])) .ap(List([‘large‘, ‘medium‘, ‘small‘])); console.log(res1) //List [ "teeshirt - large", "teeshirt - medium", "teeshirt - small", "sweater - large", "sweater - medium", "sweater - small" ]
[Compose] 17. List comprehensions with Applicative Functors
标签：bsp com list table res cat compose ann with
原文地址：http://www.cnblogs.com/Answer1215/p/6208893.html
