diff options
Diffstat (limited to 'parser.lisp')
| -rw-r--r-- | parser.lisp | 16 |
1 files changed, 10 insertions, 6 deletions
diff --git a/parser.lisp b/parser.lisp index 30c68fd..04d3f2b 100644 --- a/parser.lisp +++ b/parser.lisp @@ -14,6 +14,10 @@ place message) +(defstruct (normal-failure (:include failure))) + +(defstruct (critical-failure (:include failure))) + (defun new (tree) (lambda (input) (make-parsing :tree tree :left input))) @@ -27,16 +31,16 @@ (defun fail (&optional (message "Unknown error.")) (lambda (input) - (make-failure :place input :message message))) + (make-critical-failure :place input :message message))) (defun either (first-parser &rest other-parsers) (lambda (input) (labels ((either-rec (body) (if (cdr body) (let ((r (funcall (car body) input))) - (if (parsing-p r) - r - (either-rec (cdr body)))) + (if (normal-failure-p r) + (either-rec (cdr body)) + r)) (funcall (car body) input)))) (either-rec (cons first-parser other-parsers))))) @@ -46,8 +50,8 @@ (let ((c (input::element input))) (if (funcall predicate c) (make-parsing :tree c :left (input::advance input)) - (make-failure :place input :message "Predicate not satisfied."))) - (make-failure :place input :message "Reached end of input.")))) + (make-normal-failure :place input :message "Predicate not satisfied."))) + (make-normal-failure :place input :message "Reached end of input.")))) (defmacro comp (bindings &body body) (if (null bindings) |