From f29aac24bbf84de061ef2f9bbeb5f7180859a5b8 Mon Sep 17 00:00:00 2001
From: John Benediktsson <mrjbq7@gmail.com>
Date: Tue, 14 May 2013 09:22:14 -0700
Subject: [PATCH] formatting: adding vprintf by request.

---
 basis/formatting/formatting-tests.factor | 4 +++-
 basis/formatting/formatting.factor       | 9 +++++++++
 2 files changed, 12 insertions(+), 1 deletion(-)

diff --git a/basis/formatting/formatting-tests.factor b/basis/formatting/formatting-tests.factor
index 0d70484b0b..413a524b67 100755
--- a/basis/formatting/formatting-tests.factor
+++ b/basis/formatting/formatting-tests.factor
@@ -3,7 +3,7 @@
 USING: calendar kernel formatting tools.test system ;
 IN: formatting.tests
 
-[ "%s" printf ] must-infer 
+[ "%s" printf ] must-infer
 [ "%s" sprintf ] must-infer
 
 [ "" ] [ "" sprintf ] unit-test
@@ -21,6 +21,8 @@ IN: formatting.tests
 [ "1.2346" ] [ 1.23456789 "%.4f" sprintf ] unit-test
 [ "  1.23" ] [ 1.23456789 "%6.2f" sprintf ] unit-test
 
+{ "foo: 1 bar: 2" } [ { 1 2 3 } "foo: %d bar: %s" vsprintf ] unit-test
+
 os windows? [
     [ "1.234000e+008" ] [ 123400000 "%e" sprintf ] unit-test
     [ "-1.234000e+008" ] [ -123400000 "%e" sprintf ] unit-test
diff --git a/basis/formatting/formatting.factor b/basis/formatting/formatting.factor
index c7e51581ad..c2169bac2b 100644
--- a/basis/formatting/formatting.factor
+++ b/basis/formatting/formatting.factor
@@ -98,6 +98,15 @@ MACRO: printf ( format-string -- )
 : sprintf ( format-string -- result )
     [ printf ] with-string-writer ; inline
 
+: vprintf ( seq format-string -- )
+    parse-printf reverse! [
+        first dup string?
+        [ '[ _ write ] ] [ '[ unclip-slice @ write ] ] if
+    ] map concat call( x -- x ) drop ;
+
+: vsprintf ( seq format-string -- result )
+    [ vprintf ] with-string-writer ; inline
+
 <PRIVATE
 
 : pad-00 ( n -- string ) number>string 2 CHAR: 0 pad-head ; inline
-- 
2.34.1