diff options
Diffstat (limited to 'lisp/emacs-lisp/pcase.el')
| -rw-r--r-- | lisp/emacs-lisp/pcase.el | 18 |
1 files changed, 10 insertions, 8 deletions
diff --git a/lisp/emacs-lisp/pcase.el b/lisp/emacs-lisp/pcase.el index d111d9e41f8..63b187be02b 100644 --- a/lisp/emacs-lisp/pcase.el +++ b/lisp/emacs-lisp/pcase.el @@ -326,7 +326,8 @@ Evaluation happens sequentially as in `setq' (not in parallel). An example: (pcase-setq `((,a) [(,b)]) '((1) [(2)])) -When a PATTERN doesn't match it's VALUE, the pair is silently skipped. +VAL is presumed to match PAT. Failure to match may signal an error or go +undetected, binding variables to arbitrary values, such as nil. \(fn PATTERNS VALUE PATTERN VALUES ...)" (declare (debug (&rest [pcase-PAT form]))) @@ -348,13 +349,14 @@ When a PATTERN doesn't match it's VALUE, the pair is silently skipped. (t (pcase-compile-patterns val - (list (cons pat - (lambda (varvals &rest _) - `(setq ,@(mapcan (lambda (varval) - (let ((var (car varval)) - (val (cadr varval))) - (list var val))) - varvals))))))))) + `((,pat + . ,(lambda (varvals &rest _) + `(setq ,@(mapcan (lambda (varval) + (let ((var (car varval)) + (val (cadr varval))) + (list var val))) + varvals)))) + (pcase--dontcare . ignore)))))) (defun pcase--trivial-upat-p (upat) (and (symbolp upat) (not (memq upat pcase--dontcare-upats)))) |