X-Git-Url: https://gerrit.simantics.org/r/gitweb?p=simantics%2Fplatform.git;a=blobdiff_plain;f=bundles%2Forg.simantics.scl.runtime%2Fscl%2FPrelude.scl;h=21658862db66f34262c1852603872ff5f25291ef;hp=6966b4489d0652c61b8cde57fc7d185b75a2dd08;hb=c125a1755cc7c4a6241c3c5bf841c3db0ff2d658;hpb=2a8d452434358e28cb826744bc01755a46455afd

diff --git a/bundles/org.simantics.scl.runtime/scl/Prelude.scl b/bundles/org.simantics.scl.runtime/scl/Prelude.scl
index 6966b4489..21658862d 100644
--- a/bundles/org.simantics.scl.runtime/scl/Prelude.scl
+++ b/bundles/org.simantics.scl.runtime/scl/Prelude.scl
@@ -1879,6 +1879,17 @@ maybeToList :: Maybe a -> [a]
 maybeToList (Just a) = [a]
 maybeToList _ = [] 
 
+"""
+`takeWhile p l`, returns the longest prefix (possibly empty) of list `l` of elements that satisfy `p`
+"""
+takeWhile :: (a -> <e> Boolean) -> [a] -> <e> [a]
+takeWhile f l = loop 0 
+  where
+    len = length l
+    loop i | i == len  = l
+           | f (l!i)   = loop (i+1)
+           | otherwise = take i l
+
 partition :: (a -> <e> Boolean) -> [a] -> <e> ([a], [a])
 partition p l = runProc do
     res1 = newArrayList