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| author | Hugo Hörnquist <hugo@lysator.liu.se> | 2023-02-23 01:08:16 +0100 |
|---|---|---|
| committer | Hugo Hörnquist <hugo@lysator.liu.se> | 2023-09-11 19:58:54 +0200 |
| commit | 7bdc4a32ff775bca0158533c9e9af250f16cceb7 (patch) | |
| tree | b5d04869ec8867be717d37af97c1173d2922cd56 | |
| parent | Change `kvlist->assq` and `group-by` to return pairs. (diff) | |
| download | calp-7bdc4a32ff775bca0158533c9e9af250f16cceb7.tar.gz calp-7bdc4a32ff775bca0158533c9e9af250f16cceb7.tar.xz | |
Extend `for'-macro to allow improper list elements.
| -rw-r--r-- | module/hnh/util.scm | 13 | ||||
| -rw-r--r-- | tests/test/util.scm | 10 |
2 files changed, 23 insertions, 0 deletions
diff --git a/module/hnh/util.scm b/module/hnh/util.scm index bbb1a5ec..ea7c0dd1 100644 --- a/module/hnh/util.scm +++ b/module/hnh/util.scm @@ -133,6 +133,19 @@ b1 body ...)))]) <collection>))))) + ((for (<var> <vars> ... . <tail>) in <collection> b1 body ...) + #'(call/ec + (lambda (break) + (map ((@ (ice-9 match) match-lambda) + [(<var> <vars> ... . <tail>) + (call/ec + (lambda (raw-continue) + (let ((continue + (case-lambda + (() #f) + (args (apply raw-continue args))))) + b1 body ...)))]) + <collection>)))) ((for <var> in <collection> b1 body ...) (with-syntax ((break (datum->syntax stx 'break)) (continue (datum->syntax stx 'continue))) diff --git a/tests/test/util.scm b/tests/test/util.scm index d2fc2d81..41dbd7a3 100644 --- a/tests/test/util.scm +++ b/tests/test/util.scm @@ -51,6 +51,16 @@ (for (x c) in (zip (iota 12) (string->list "Hello, World")) x)) + (test-equal "for with improper list elements" + `(3 7) + (for (a . b) in '((1 . 2) (3 . 4)) + (+ a b))) + + (test-equal "for with longer improper list elements" + '(1 2 4) + (for (a b . c) in '((1 -1 . 1) (2 -2 . 2) (4 -4 . 4)) + (* c (+ 1 a b)))) + (test-equal "for break" 'x (for x in (iota 10) |