~ chicken-core (chicken-5) 399f9968848c2dc1d0d7e94df5e2c5a699934e53

commit 399f9968848c2dc1d0d7e94df5e2c5a699934e53
Author:     felix <felix@call-with-current-continuation.org>
AuthorDate: Tue Oct 30 10:47:15 2012 +0100
Commit:     Peter Bex <peter.bex@xs4all.nl>
CommitDate: Wed Oct 31 21:43:44 2012 +0100

    allow unsetting read-syntax
    
    Signed-off-by: Peter Bex <peter.bex@xs4all.nl>

diff --git a/library.scm b/library.scm
index ffd01914..8cb2b7e3 100644
--- a/library.scm
+++ b/library.scm
@@ -3065,9 +3065,13 @@ EOF
 	     (unless (##sys#slot crt slot)
 	       (##sys#setslot crt slot (##sys#make-vector 256 #f)) )
 	     (##sys#check-char chr loc)
-	     (let ([i (char->integer chr)])
+	     (let ((i (char->integer chr)))
 	       (##sys#check-range i 0 256 loc)
-	       (##sys#setslot (##sys#slot crt slot) i (wrap proc)) ) ) ) ) )
+              (cond (proc
+                     (##sys#check-closure proc loc)
+                     (##sys#setslot (##sys#slot crt slot) i (wrap proc)))
+                    (else
+                     (##sys#setslot (##sys#slot crt slot) i #f))))))))
  
   (set! set-read-syntax!
     (syntax-setter
diff --git a/manual/Unit library b/manual/Unit library
index 2bc10457..232d42c9 100644
--- a/manual/Unit library	
+++ b/manual/Unit library	
@@ -1224,6 +1224,8 @@ To disable built-in read-syntax, define a handler that triggers an error (for ex
 Similar to {{set-read-syntax!}}, but allows defining new {{#<CHAR> ...}} reader syntax.
 If the first argument is a symbol, then this procedure is equivalent to {{set-read-syntax!}}.
 
+{{PROC}} may be {{#f}} to disable previously defined "sharp" read syntax.
+
 
 ==== set-parameterized-read-syntax!
 
@@ -1235,6 +1237,8 @@ arguments: the input port and the number preceding
 the dispatching character.
 If the first argument is a symbol, then this procedure is equivalent to {{set-read-syntax!}}.
 
+{{PROC}} may be {{#f}} to disable previously defined parameterized read syntax.
+
 
 ==== copy-read-table
 
diff --git a/types.db b/types.db
index b7b61218..2e6e45df 100644
--- a/types.db
+++ b/types.db
@@ -1034,13 +1034,22 @@
 (set-gc-report! (#(procedure #:clean) set-gc-report! (*) undefined))
 
 (set-parameterized-read-syntax!
- (#(procedure #:clean #:enforce) set-parameterized-read-syntax! (char (procedure (input-port fixnum) . *)) undefined))
+ (#(procedure #:clean #:enforce) set-parameterized-read-syntax!
+  (char (or boolean (procedure (input-port fixnum) . *)))
+  undefined))
 
 (set-port-name! (#(procedure #:clean #:enforce) set-port-name! (port string) undefined)
 		((port string) (##sys#setslot #(1) '3 #(2))))
 
-(set-read-syntax! (#(procedure #:clean #:enforce) set-read-syntax! (char (procedure (input-port) . *)) undefined))
-(set-sharp-read-syntax! (#(procedure #:clean #:enforce) set-sharp-read-syntax! (char (procedure (input-port) . *)) undefined))
+(set-read-syntax!
+ (#(procedure #:clean #:enforce) set-read-syntax!
+  (char (or boolean (procedure (input-port) . *)))
+  undefined))
+
+(set-sharp-read-syntax!
+ (#(procedure #:clean #:enforce) set-sharp-read-syntax!
+  (char (or boolean (procedure (input-port) . *))) undefined))
+
 (setter (#(procedure #:clean #:enforce) setter (procedure) procedure))
 (signal (procedure signal (*) . *))
 (signum (#(procedure #:clean #:enforce) signum (number) number))