1 files changed, 93 insertions, 0 deletions
diff --git a/stdlib/glob.tl b/stdlib/glob.tl
new file mode 100644
index 00000000..c23845a3
--- /dev/null
+++ b/stdlib/glob.tl
@@ -0,0 +1,93 @@
+;; Copyright 2023
+;; Kaz Kylheku <kaz@kylheku.com>
+;; Vancouver, Canada
+;; All rights reserved.
+;;
+;; Redistribution and use in source and binary forms, with or without
+;; modification, are permitted provided that the following conditions are met:
+;;
+;; 1. Redistributions of source code must retain the above copyright notice,
+;;    this list of conditions and the following disclaimer.
+;;
+;; 2. Redistributions in binary form must reproduce the above copyright notice,
+;;    this list of conditions and the following disclaimer in the documentation
+;;    and/or other materials provided with the distribution.
+;;
+;; THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+;; AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+;; IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+;; ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
+;; LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+;; CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+;; SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+;; INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+;; CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+;; ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+;; POSSIBILITY OF SUCH DAMAGE.
+
+(defun brace-expand (str)
+  (bexp-expand (bexp-parse str)))
+
+(defstruct bexp-parse-ctx ()
+  str
+  toks)
+
+(defun bexp-parse (str)
+  (let ((ctx (new bexp-parse-ctx
+                   str str
+                   toks (remqual "" (tok #/([{},]|{}|\\\\|\\.)/ t str)))))
+    (build
+      (whilet ((next (pop ctx.toks)))
+        (add
+          (if (equal next "{")
+            (bexp-parse-brace ctx)
+            next))))))
+
+(defun bexp-parse-brace (ctx)
+  (buildn
+    (caseq (whilet ((next (pop ctx.toks)))
+             (casequal next
+               ("{" (add (bexp-parse-brace ctx)))
+               ("}" (return :ok))
+               (t (add next))))
+      (:ok
+        (cond
+          ((memqual "," (get))
+           (flow (get)
+             (split* @1 (op where (op equal ",")))
+             (cons '/)))
+          (t
+            (add* "{")
+            (add "}")
+            (get))))
+      (nil
+        (add* "{")
+        (get)))))
+
+(defun bexp-expand (tree : (path (new list-builder)))
+  (build
+    (match-case tree
+      (() (add (cat-str path.(get))))
+      (((/ . @alt) . @rest)
+       (let ((saved-path path.(get)))
+         (each ((elem alt))
+           path.(oust saved-path)
+           (pend (bexp-expand (cons elem rest) path)))))
+      ((@(consp @succ) . @rest)
+       (pend (bexp-expand (append succ rest) path)))
+      ((@head . @rest)
+       path.(add head)
+       (pend (bexp-expand rest path))))))
+
+
+(defun glob* (pattern-or-patterns : (flags 0))
+  (let ((xflags (logior flags sys:glob-xstar))
+        (patterns (if (listp pattern-or-patterns)
+                    pattern-or-patterns
+                    (list pattern-or-patterns))))
+    (if (or (logtest flags glob-xnobrace)
+            (null (find-if (op find #\{) patterns)))
+      (glob patterns xflags)
+      (let ((xpatterns [mappend brace-expand patterns]))
+        (append-each ((p xpatterns))
+          (glob p xflags))))))