sequences.extras: adding extract!.

It's similar to reject! but returns the items that were removed.
factor · Jun 28, 2019 · 81f2e9a · 81f2e9a
1 parent 00a0edb
commit 81f2e9a
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diff --git a/extra/sequences/extras/extras-tests.factor b/extra/sequences/extras/extras-tests.factor
@@ -281,3 +281,5 @@ tools.test vectors vocabs ;
 { 0 } [ { 1 2 3 4 } [ 5 > ] count-tail ] unit-test
 { 2 } [ { 1 2 3 4 } [ 2 > ] count-tail ] unit-test
 { 4 } [ { 1 2 3 4 } [ 5 < ] count-tail ] unit-test
+
+{ SBUF" aco" SBUF" ftr"  } [ SBUF" factor" dup [ even? ] extract! ] unit-test
diff --git a/extra/sequences/extras/extras.factor b/extra/sequences/extras/extras.factor
@@ -649,3 +649,7 @@ PRIVATE>
 
 : interleaved ( seq glue -- newseq )
     over interleaved-as ;
+
+: extract! ( ... seq quot: ( ... elt -- ... ? ) -- ... seq )
+    [ dup ] compose over [ length ] keep new-resizable
+    [ [ push-if ] 2curry reject! ] keep swap like ; inline