1 files changed, 54 insertions, 0 deletions
diff --git a/stdlib/doloop.tl b/stdlib/doloop.tl
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+++ b/stdlib/doloop.tl
@@ -0,0 +1,54 @@
+;; Copyright 2017-2021
+;; 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 sys:expand-doloop (f vars cexp body)
+  (let ((xvars (mapcar (tc
+                         (((:whole w v i s . r))
+                          (if r (compile-error f "excess elements in ~s" w) w))
+                         (((:whole w v i . r))
+                          (if r
+                            (compile-error f "bad variable clause syntax ~s" w)
+                            ^(,v ,i ,i)))
+                         (((:whole w v . r))
+                          (if r
+                            (compile-error f "bad variable clause syntax ~s" w)
+                            ^(,v nil ,v)))
+                         ((v) ^(,v nil ,v)))
+                       vars))
+        (pllel (eq (car f) 'doloop)))
+    ^(,(if pllel 'for 'for*)
+       ,(mapcar (aret ^(,@1 ,@2)) xvars)
+       ,cexp
+       ((,(if pllel 'pset 'set) ,*(mappend (ado unless (eq @1 @3)
+                                             ^(,@1 ,@3))
+                                           xvars)))
+       (tagbody ,*body))))
+
+(defmacro doloop (:form f vars cexp . body)
+  (sys:expand-doloop f vars cexp body))
+
+(defmacro doloop* (:form f vars cexp . body)
+  (sys:expand-doloop f vars cexp body))