X-Git-Url: https://www.chiark.greenend.org.uk/ucgi/~mdw/git/sod/blobdiff_plain/1c2db39a35b4efe99594b2a53737d4f0971d01d8..b5911ce8da34bfdd5c4515b44fd2efce7c9c233f:/src/lexer-proto.lisp

diff --git a/src/lexer-proto.lisp b/src/lexer-proto.lisp
index 60235ff..a811298 100644
--- a/src/lexer-proto.lisp
+++ b/src/lexer-proto.lisp
@@ -129,7 +129,7 @@ (defparse skip-until (:context (context token-scanner-context)
 (export 'error)
 (defparse error (:context (context token-scanner-context)
 		 (&key ignore-unconsumed force-progress)
-		 sub &optional (recover t))
+		 sub &optional (recover t) &body body)
   "Try to parse SUB; if it fails then report an error, and parse RECOVER.
 
    This is the main way to recover from errors and continue parsing.  Even
@@ -148,7 +148,8 @@ (defparse error (:context (context token-scanner-context)
 			(parser () ,sub)
 			(parser () ,recover)
 			:ignore-unconsumed ,ignore-unconsumed
-			:force-progress ,force-progress))
+			:force-progress ,force-progress
+			:action ,(and body `(lambda () ,@body))))
 
 (export 'must)
 (defparse must (:context (context token-scanner-context)