From 5a8f9284ab294a680b6880be08f05e90f9bcca3e Mon Sep 17 00:00:00 2001
From: Doug Coleman <doug.coleman@gmail.com>
Date: Thu, 28 Sep 2017 22:41:21 -0500
Subject: [PATCH] sequences.extras: add count-head and count-tail

---
 extra/sequences/extras/extras.factor | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/extra/sequences/extras/extras.factor b/extra/sequences/extras/extras.factor
index b964e52af8..da8260b5de 100644
--- a/extra/sequences/extras/extras.factor
+++ b/extra/sequences/extras/extras.factor
@@ -620,3 +620,10 @@ PRIVATE>
 : drop-while ( ... seq quot: ( ... elt -- ... ? ) -- tail-slice )
     [ '[ @ not ] find drop ] 2keep drop swap
     [ dup length ] unless* tail-slice ; inline
+
+: count-head ( seq quot -- n )
+    [ not ] compose find drop ; inline
+
+: count-tail ( seq quot -- n )
+    [ not ] compose [ find-last drop ] 2keep drop
+    length swap [ - 1 - ] when* ; inline
\ No newline at end of file