Fixed documentation: expand-all-expanders-of-type should be expand-syntax-tree-with-expanders-of-type

Remove the extra use-site scope on the body of define-?-expander.

private/define-expanders.rkt

@@ -27,7 +27,8 @@
                            (define-for-syntax (make-?-expander transformer)
                              (expander ?-expander-type transformer))
                            (define-for-syntax (?-expander? v)
-                             (expander-of-type? ?-expander-type v))
+                             (and (expander? v)
+                                  (expander-of-type? ?-expander-type v)))
                            (define-syntax define-?-expander
                              (syntax-parser
                                [(_ expander-name:id transformer:expr)

private/define-expanders.scrbl

@@ -23,6 +23,7 @@ expanders for use with other macros.
    environment}
  @item{@code{expand-all-id-expanders} - a procedure bound at phase
    @; TODO: expand-all-expanders-of-type is not documented
-   level 1 that's equivalent to @racket[expand-all-expanders-of-type] with
-   the @code{id-expander-type} as the type argument}
+   level 1 that's equivalent to
+   @racket[expand-syntax-tree-with-expanders-of-type] with the
+   @code{id-expander-type} as the type argument}
  ]}

private/expanders.rkt

@@ -4,16 +4,14 @@
          syntax/parse
          syntax/stx
          predicates
-         fancy-app)
+         fancy-app
+         racket/syntax)
 
 (provide (struct-out expander)
          (contract-out
           [expander-of-type? (-> expander-type? expander? boolean?)]
           [expand-syntax-tree-with-expanders-of-type (-> expander-type? syntax? syntax?)]))
 
-(define (maybe-syntax-local-value stx)
-  (syntax-local-value stx (λ () #f)))
-
 (struct expander (type transformer))
 
 (define (expander-of-type? type expander)
@@ -22,12 +20,12 @@
 (define (expander-stx? v)
   (and (syntax? v)
        (syntax-parse v
-         [(id:id _ ...) (expander? (maybe-syntax-local-value #'id))]
+         [(id:id . _) (syntax-local-value/record #'id expander?)]
          [_ #f])))
 
 (define (expander-stx->expander expander-stx)
   (syntax-parse expander-stx
-    [(id:id _ ...) (maybe-syntax-local-value #'id)]))
+    [(id:id . _) (syntax-local-value/record #'id expander?)]))
 
 (define (expander-stx-of-type? type v)
   (and (expander-stx? v)
@@ -47,6 +45,7 @@
 
 (define (expand-syntax-tree-with-expanders-of-type type stx)
   (define not-expander-stx-of-type? (not? (expander-stx-of-type? type _)))
-  (expand-syntax-tree not-expander-stx-of-type?
-                      call-expander-transformer
-                      stx))
+  (with-disappeared-uses 
+   (expand-syntax-tree not-expander-stx-of-type?
+                       call-expander-transformer
+                       stx)))

test/test-arrows.rkt

@@ -0,0 +1,13 @@
+#lang racket
+(require generic-syntax-expanders rackunit)
+(define-expander-type foo)
+(define-foo-expander foo1 (λ _ #''ok))
+(define-syntax (bar stx)
+  (syntax-case stx ()
+    [(_ body)
+     (expand-all-foo-expanders #'body)]))
+;; When hovering "foo1" in the code below with the mouse, an arrow should 
+;; be shown in DrRacket from the foo1 in (define-foo-expander foo1 …) above.
+;; This is not automatically checked, as it would be difficult/brittle to check
+;; for the syntax property. Patches welcome.
+(check-equal? (bar (foo1)) 'ok)

test/test-call-with-dotted-last.rkt

@@ -0,0 +1,22 @@
+#lang racket
+
+(require generic-syntax-expanders
+         (for-syntax syntax/parse)
+         rackunit)
+
+(define-expander-type foo)
+
+(define-foo-expander some-foo-expander
+  (syntax-parser
+    [(_ a:id b:id c:id . d:id) #'(d c b a)]))
+
+(define-syntax (test-foo-expander stx)
+  (syntax-parse stx
+    [(_ e:expr)
+     #`'#,(expand-all-foo-expanders #'e)]))
+
+(test-equal?
+ "Check that some-foo-expander accepts being called
+ when it is the first item of a dotted list"
+ (test-foo-expander (some-foo-expander x y z . t))
+ '(t z y x))

test/test-foo-mixin-expander-predicate.rkt

@@ -0,0 +1,61 @@
+#lang racket
+
+(require generic-syntax-expanders
+         (for-syntax syntax/parse
+                     rackunit))
+(require (for-syntax generic-syntax-expanders))
+(define-expander-type foo)
+(define-expander-type other)
+(define-foo-expander foo-exp (λ (stx) #''foo-exp-is-a-foo-expander))
+(define-other-expander other-exp (λ (stx) #''other-exp-is-not-a-foo-expander))
+(define-syntax not-an-expander 'syntax-local-value-is-not-an-expander)
+(begin-for-syntax
+  (test-not-exn
+   "Check that foo-expander? can be passed any value, not just an expander?"
+   (λ ()
+     (foo-expander? 123)
+     (void)))
+  
+  (test-false
+   "Check that (static foo-expander?) rejects syntax that is not an identifier?"
+   (syntax-parse #'(definitely not-a-foo-expander)
+     [(~var exp (static foo-expander? "a foo expander")) #t]
+     [_ #f]))
+  
+  (test-false
+   "Check that (static foo-expander?) rejects an id without syntax-local-value"
+   (syntax-parse #'no-syntax-local-value
+     [(~var exp (static foo-expander? "a foo expander")) #t]
+     [_ #f]))
+
+  (test-begin
+   (test-false
+    "Check that foo-expander? rejects an id which is not an expander?"
+    (foo-expander? (syntax-local-value #'not-an-expander)))
+   (test-false
+    "Check that foo-expander? rejects an id which is not an expander?"
+    (syntax-parse #'not-an-expander
+      [(~var exp (static foo-expander? "a foo expander")) #t]
+      [_ #f])))
+
+  (test-begin
+   (test-false
+    (string-append "Check that foo-expander? rejects an id which is an"
+                   " expander? but not a foo-expander?")
+    (foo-expander? (syntax-local-value #'other-exp)))
+   (test-false
+    (string-append "Check that foo-expander? rejects an id which is an"
+                   " expander? but not a foo-expander?")
+    (syntax-parse #'other-exp
+      [(~var exp (static foo-expander? "a foo expander")) #t]
+      [_ #f])))
+
+  (test-begin
+   (test-true
+    "Check that foo-expander? accepts an id which is a foo-expander?"
+    (foo-expander? (syntax-local-value #'foo-exp)))
+   (test-true
+    "Check that foo-expander? accepts an id which is a foo-expander?"
+    (syntax-parse #'foo-exp
+      [(~var exp (static foo-expander? "a foo expander")) #t]
+      [_ #f]))))