| 1 | ;;; installed-scm-file |
| 2 | |
| 3 | ;;;; Copyright (C) 2001, 2006 Free Software Foundation, Inc. |
| 4 | ;;;; |
| 5 | ;;;; This library is free software; you can redistribute it and/or |
| 6 | ;;;; modify it under the terms of the GNU Lesser General Public |
| 7 | ;;;; License as published by the Free Software Foundation; either |
| 8 | ;;;; version 2.1 of the License, or (at your option) any later version. |
| 9 | ;;;; |
| 10 | ;;;; This library is distributed in the hope that it will be useful, |
| 11 | ;;;; but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 12 | ;;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 13 | ;;;; Lesser General Public License for more details. |
| 14 | ;;;; |
| 15 | ;;;; You should have received a copy of the GNU Lesser General Public |
| 16 | ;;;; License along with this library; if not, write to the Free Software |
| 17 | ;;;; Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
| 18 | ;;;; |
| 19 | |
| 20 | (define-module (ice-9 stack-catch) |
| 21 | :export (stack-catch)) |
| 22 | |
| 23 | (define (stack-catch key thunk handler) |
| 24 | "Like @code{catch}, invoke @var{thunk} in the dynamic context of |
| 25 | @var{handler} for exceptions matching @var{key}, but also save the |
| 26 | current stack state in the @var{the-last-stack} fluid, for the purpose |
| 27 | of debugging or re-throwing of an error. If thunk throws to the |
| 28 | symbol @var{key}, then @var{handler} is invoked this way:\n |
| 29 | @example |
| 30 | (handler key args ...) |
| 31 | @end example\n |
| 32 | @var{key} is a symbol or #t.\n |
| 33 | @var{thunk} takes no arguments. If @var{thunk} returns normally, that |
| 34 | is the return value of @code{catch}.\n |
| 35 | Handler is invoked outside the scope of its own @code{catch}. If |
| 36 | @var{handler} again throws to the same key, a new handler from further |
| 37 | up the call chain is invoked.\n |
| 38 | If the key is @code{#t}, then a throw to @emph{any} symbol will match |
| 39 | this call to @code{catch}." |
| 40 | (catch key |
| 41 | thunk |
| 42 | handler |
| 43 | lazy-handler-dispatch)) |