syntax/parse:

fixed bug: splicing-stxclass immediately within ellipses
  added tests, docs for local-conventions

svn: r17944

collects/syntax/private/stxparse/parse.ss

@@ -369,6 +369,7 @@
         #'#s(pat:compound attrs #:pair (head-part tail-part)))])))
 
 ;; (parse:H id FCE HeadPattern id id expr) : expr
+;; x must not alias rest
 (define-syntax (parse:H stx)
   (syntax-case stx ()
     [(parse:H x fc head rest rest-fc k)
@@ -471,11 +472,11 @@
                      [(attr-repc ...) attr-repcs])
          (define-pattern-variable alt-map #'((id . alt-id) ...))
          (define-pattern-variable loop-k
-           #'(dots-loop dx loop-fc* enclosing-fail rel-rep ... alt-id ...))
+           #'(dots-loop dx* loop-fc* enclosing-fail rel-rep ... alt-id ...))
          #`(let ()
              (define (dots-loop dx loop-fc loop-fail rel-rep ... alt-id ...)
                (with-enclosing-fail loop-fail
-                 (try (parse:EH dx loop-fc head head-repc loop-fc* alt-map head-rep
+                 (try (parse:EH dx loop-fc head head-repc dx* loop-fc* alt-map head-rep
                                 loop-k)
                       ...
                       (cond [(< rel-rep (rep:min-number rel-repc))
@@ -494,7 +495,7 @@
 ;;           RepConstraint/#f expr) : expr
 (define-syntax (parse:EH stx)
   (syntax-case stx ()
-    [(parse:EH x fc head repc fc* alts rep k0)
+    [(parse:EH x fc head repc x* fc* alts rep k0)
      (let ()
        (define-pattern-variable k
          (let* ([main-attrs (wash-iattrs (pattern-attrs (wash #'head)))]
@@ -511,11 +512,11 @@
              #`(let ([alt-id (rep:combine repc (attribute id) alt-id)] ...)
                  k0))))
        (syntax-case #'repc ()
-         [#f #`(parse:H x fc head x fc* k)]
-         [_  #`(parse:H x fc head x fc*
+         [#f #`(parse:H x fc head x* fc* k)]
+         [_  #`(parse:H x fc head x* fc*
                         (if (< rep (rep:max-number repc))
                             (let ([rep (add1 rep)]) k)
-                            (fail x
+                            (fail x*
                                   #:expect (expectation-of-reps/too-many rep repc)
                                   #:fce fc*)))]))]))
 

collects/syntax/scribblings/parse.scrbl

@@ -357,7 +357,8 @@ variables that do not explicitly specify a syntax class.
 
 Uses the @tech{conventions} specified. The advantage of
 @scheme[#:local-conventions] over @scheme[#:conventions] is that local
-conventions can be in the scope of syntax-class parameter bindings.
+conventions can be in the scope of syntax-class parameter
+bindings. See the section on @tech{conventions} for examples.
 }
 
 Each clause consists of a @tech{syntax pattern}, an optional sequence
@@ -751,6 +752,28 @@ class.
    (syntax->datum #'(x0 (x ...) n0 (n ...)))])
 ]
 
+Local conventions, introduced with the @scheme[#:local-conventions]
+keyword argument of @scheme[syntax-parse] and syntax class
+definitions, may refer to local bindings:
+
+@myexamples[
+(define-syntax-class (nat> bound)
+  (pattern n:nat
+           #:fail-unless (> (syntax-e #'n) bound)
+                         (format "expected number > ~s" bound)))
+
+(define-syntax-class (natlist> bound)
+  #:local-conventions ([N (nat> bound)])
+  (pattern (N ...)))
+
+(define (parse-natlist> bound x)
+  (syntax-parse x
+    #:local-conventions ([NS (natlist> bound)])
+    [NS 'ok]))
+(parse-natlist> 0 #'(1 2 3))
+(parse-natlist> 5 #'(8 6 4 2))
+]
+
 }
 
 @;{----------}

collects/tests/stxparse/more-tests.ss

@@ -189,19 +189,19 @@
 
 (tcerr "parse-ehpat/bounds: min"
        (syntax-parser
-        [((~bounds x 1.0 9) ...) 'ok])
+        [((~between x 1.0 9) ...) 'ok])
        #rx"^syntax-parser: "
        #rx"expected exact nonnegative integer")
 
 (tcerr "parse-ehpat/bounds: max"
        (syntax-parser
-        [((~bounds x 1 "foo") ...) 'ok])
+        [((~between x 1 "foo") ...) 'ok])
        #rx"^syntax-parser: "
        #rx"expected exact nonnegative integer")
 
 (tcerr "parse-ehpat/bounds: min>max"
        (syntax-parser
-        [((~bounds x 3 2) ...) 'ok])
+        [((~between x 3 2) ...) 'ok])
        #rx"^syntax-parser: "
        #rx"minimum larger than maximum")
 

collects/tests/stxparse/stxclass.ss

@@ -210,3 +210,26 @@
     (syntax-parse #'(4 -1) #:conventions (nat-convs)
       [(N ...) (void)]))
   (error 'test-conv1 "didn't work"))
+
+;; Local conventions
+
+(define-syntax-class (nats> bound)
+  #:local-conventions ([N (nat> bound)])
+  (pattern (N ...)))
+
+(define (p1 bound x)
+  (syntax-parse x
+    #:local-conventions ([ns (nats> bound)])
+    [ns 'yes]
+    [_ 'no]))
+
+(eq? (p1 0 #'(1 2 3)) 'yes)
+(eq? (p1 2 #'(1 2 3)) 'no)
+
+;; Regression (2/2/2010)
+
+(define-splicing-syntax-class twoseq
+  (pattern (~seq a b)))
+
+(syntax-parse #'(1 2 3 4)
+  [(x:twoseq ...) 'ok])