From d8567468d2e8ea442086658806c8b098e6f02295 Mon Sep 17 00:00:00 2001 From: Gregor Kleen Date: Sun, 29 Mar 2015 05:32:34 +0200 Subject: update - functions existed all along --- posts/blog-rss.md | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/posts/blog-rss.md b/posts/blog-rss.md index 559a6c6..f7116a9 100644 --- a/posts/blog-rss.md +++ b/posts/blog-rss.md @@ -23,3 +23,13 @@ Along the way two helper functions were introduced — if an implementation of t (<-->) :: [(a -> a)] -> a -> a [] <--> x = x (f:fs) <--> x = fs <--> (f x) + +== Update + + import Control.Applicative ((<*>), pure) + + (<->) fs = (<*>) fs . pure + + (<-->) = flip $ foldl (.) id + +Thanks, viktor. \ No newline at end of file -- cgit v1.2.3