From: Hannu Niemistö <hannu.niemisto@semantum.fi>
Date: Fri, 6 Oct 2017 06:56:59 +0000 (+0300)
Subject: (refs #7531) Functions first and last to Prelude
X-Git-Tag: v1.31.0~138^2
X-Git-Url: https://gerrit.simantics.org/r/gitweb?a=commitdiff_plain;h=9dada94874a646bc63fc73ed1fd431456ce50889;p=simantics%2Fplatform.git

(refs #7531) Functions first and last to Prelude

Change-Id: Ic8839efc97a619658e570f435c23ac0c1d9b3e18
---

diff --git a/bundles/org.simantics.scl.runtime/scl/Prelude.scl b/bundles/org.simantics.scl.runtime/scl/Prelude.scl
index f06acb29f..8fcd3ced1 100644
--- a/bundles/org.simantics.scl.runtime/scl/Prelude.scl
+++ b/bundles/org.simantics.scl.runtime/scl/Prelude.scl
@@ -1162,6 +1162,14 @@ class IndexedSequence f where
     "`seq ! i` returns the `i`th element of the sequence `seq`. Indexing starts from zero."
     (!) :: f a -> Integer -> a
 
+"Returns the first element of a sequence"
+@inline
+first l = l!0
+
+"Returns the last element of a sequence"
+@inline
+last l = l!(length l-1)
+
 instance IndexedSequence [] where
     (!) = getList