From: Camil Staps <info@camilstaps.nl>
Date: Thu, 12 Mar 2015 12:38:27 +0000 (+0100)
Subject: Don't know how to make takeWhile work nicely...
X-Git-Url: https://git.martlubbers.net/?a=commitdiff_plain;h=635235781923962beb50fb608a3d6e5b35c4cf38;p=fp1415.git

Don't know how to make takeWhile work nicely...
---

diff --git a/week5/camil/Origami.icl b/week5/camil/Origami.icl
index d844d2c..74362a9 100644
--- a/week5/camil/Origami.icl
+++ b/week5/camil/Origami.icl
@@ -2,21 +2,23 @@ module Origami
 
 import StdEnv
 
-/*Start			= and
+Start			= and
 				  [ sum`       [1 .. 5]                 == sum       [1 .. 5]
 				  , prod`      [1 .. 5]                 == prod      [1 .. 5]
 				  , flatten`   [[],[1],[1,2],[1,2,3]]   == flatten   [[],[1],[1,2],[1,2,3]]
 				  , reverse`   [1 .. 5]                 == reverse   [1 .. 5]
 				  , takeWhile` ((<>) 0) [1,2,3,0,4,5,6] == takeWhile ((<>) 0) [1,2,3,0,4,5,6]
 				  , maxList`   [1 .. 5]                 == maxList   [1 .. 5]
-				  ]*/
-Start = takeWhile` ((<>) 0) [1,2,3,0,4,5,6]
+				  ]
 
 sum`			= foldr (+) 0
 prod`			= foldr (*) 1
 flatten`		= foldr (++) []
 length`			= foldl (\l e = l + 1) 0
 reverse`		= foldl (\xs x = [x:xs]) []
-takeWhile` p		= foldr (\x xs = if (p x) [x:xs] xs) []
+takeWhile` _ [] 	= []
+takeWhile` p xs
+	| p (xs!!0)	= take (maxList [i \\ i <- [0..length xs-1] | foldr (&&) True [p (xs!!j) \\ j <- [0..i]]] + 1) xs
+	| otherwise	= []
 maxList` []		= undef
 maxList` [x:xs]		= foldr max x xs