sorting.extras: add some docs.

diff --git a/extra/sorting/extras/extras-docs.factor b/extra/sorting/extras/extras-docs.factor
new file mode 100644 (file)
index 0000000..9b54e02
--- /dev/null
+++ b/extra/sorting/extras/extras-docs.factor
@@ -0,0 +1,6 @@
+USING: help.markup help.syntax sequences ;
+IN: sorting.extras
+
+HELP: map-sort
+{ $values { "seq" sequence } { "quot" { $quotation ( ... elt -- ... key ) } } { "sortedseq" "a new sorted sequence" } }
+{ $description "Sort the elements of " { $snippet "seq" } " a sequence using " { $snippet "quot" } " as a key function." } ;