Add Predicate type

2018-12-19 17:08:09 +09:00
parent 78ec06bda3
commit 8025b121af
2 changed files with 6 additions and 3 deletions
--- a/src/prelude/relation.ts
+++ b/src/prelude/relation.ts
@@ -1,3 +1,5 @@
+export type Predicate<T> = (x: T) => boolean;
+
 export type Relation<T, U> = (x: T, y: U) => boolean;

 export type EndoRelation<T> = Relation<T, T>;