combinators.extras: Add twice, thrice words.

diff --git a/extra/combinators/extras/authors.txt b/extra/combinators/extras/authors.txt
new file mode 100644 (file)
index 0000000..7c1b2f2
--- /dev/null
+++ b/extra/combinators/extras/authors.txt
@@ -0,0 +1 @@
+Doug Coleman

diff --git a/extra/combinators/extras/extras-tests.factor b/extra/combinators/extras/extras-tests.factor
new file mode 100644 (file)
index 0000000..c72b493
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+++ b/extra/combinators/extras/extras-tests.factor
@@ -0,0 +1,13 @@
+! Copyright (C) 2013 Doug Coleman.
+! See http://factorcode.org/license.txt for BSD license.
+USING: tools.test combinators.extras sequences ;
+IN: combinators.extras.tests
+
+{ "a b" }
+[ "a" "b" [ " " glue ] once ] unit-test
+
+{ "a b c" }
+[ "a" "b" "c" [ " " glue ] twice ] unit-test
+
+{ "a b c d" }
+[ "a" "b" "c" "d" [ " " glue ] thrice ] unit-test

diff --git a/extra/combinators/extras/extras.factor b/extra/combinators/extras/extras.factor
new file mode 100644 (file)
index 0000000..03025b8
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+++ b/extra/combinators/extras/extras.factor
@@ -0,0 +1,8 @@
+! Copyright (C) 2013 Doug Coleman.
+! See http://factorcode.org/license.txt for BSD license.
+USING: kernel ;
+IN: combinators.extras
+
+: once ( quot -- ) call ; inline
+: twice ( quot -- ) dup [ call ] dip call ; inline
+: thrice ( quot -- ) dup dup [ call ] 2dip [ call ] dip call ; inline