From d6065ab851766f3d11b95ae19a8027f494f530a5 Mon Sep 17 00:00:00 2001
From: Matthew Flatt <mflatt@racket-lang.org>
Date: Fri, 21 Sep 2001 23:28:09 +0000
Subject: [PATCH] .

original commit: 52e08facacdf308d88db5e7522871dd876d132bb
---
 collects/mzlib/private/stxset.ss | 101 +++++++++++++++++++++++++++++++
 1 file changed, 101 insertions(+)
 create mode 100644 collects/mzlib/private/stxset.ss

diff --git a/collects/mzlib/private/stxset.ss b/collects/mzlib/private/stxset.ss
new file mode 100644
index 0000000..9439a4d
--- /dev/null
+++ b/collects/mzlib/private/stxset.ss
@@ -0,0 +1,101 @@
+
+(module stxset mzscheme
+
+  (require-for-syntax (lib "kerncase.ss" "syntax"))
+
+  (provide finish-syntax-set)
+
+  ;; Used in the expansion of `define-syntax-set' from "etc.ss"
+  (define-syntax (finish-syntax-set stx)
+    (syntax-case stx ()
+      [(_ stx)
+       (let ([stx (syntax stx)])
+	 (syntax-case stx ()
+	   [(_ (id ...) defn ...)
+	    ;; The ids have already been checked --------------------
+	    (let ([ids (syntax->list (syntax (id ...)))])
+	      (let ([internal-ids (map (lambda (id)
+					 (datum->syntax-object
+					  id
+					  (string->symbol (format "~a/proc" (syntax-e id)))
+					  id))
+				       ids)])
+		;; Check defns (requires expand) ---------
+		(let* ([defns (let loop ([defns (syntax->list (syntax (defn ...)))])
+				(apply 
+				 append
+				 (map
+				  (lambda (defn)
+				    (let ([defn (local-expand
+						 defn
+						 'internal-define
+						 (kernel-form-identifier-list (quote-syntax here)))])
+				      (syntax-case defn (define-values define-syntaxes begin)
+					[(define-values (id ...) expr)
+					 (andmap identifier? (syntax->list (syntax (id ...))))
+					 (list defn)]
+					[(define-values . _)
+					 (raise-syntax-error
+					  #f
+					  "bad definition"
+					  stx
+					  defn)]
+					[(define-syntaxes (id ...) expr)
+					 (andmap identifier? (syntax->list (syntax (id ...))))
+					 (list defn)]
+					[(define-syntaxes . _)
+					 (raise-syntax-error
+					  #f
+					  "bad definition"
+					  stx
+					  defn)]
+					[(begin defn ...)
+					 (loop (syntax->list (syntax (defn ...))))]
+					[(begin . _)
+					 (raise-syntax-error
+					  #f
+					  "bad `begin'"
+					  stx
+					  defn)]
+					[else
+					 (raise-syntax-error
+					  #f
+					  "not a definition"
+					  stx
+					  defn)])))
+				  defns)))]
+		       
+		       [def-ids (apply append (map (lambda (defn)
+						     (syntax-case defn ()
+						       [(_ (id ...) expr)
+							(syntax->list (syntax (id ...)))]))
+						   defns))]
+		       [val-ids (apply append (map (lambda (defn)
+						     (syntax-case defn (define-values)
+						       [(define-values (id ...) expr)
+							(syntax->list (syntax (id ...)))]
+						       [_else null]))
+						   defns))])
+		  (let ([dup (check-duplicate-identifier def-ids)])
+		    (when dup
+		      (raise-syntax-error
+		       #f
+		       "duplicate defined identifier"
+		       stx
+		       dup)))
+		  ;; Check that declared are defined ---------
+		  (for-each (lambda (id)
+			      (unless (check-duplicate-identifier (cons id val-ids))
+				(raise-syntax-error
+				 #f
+				 "expected identifier is not defined"
+				 stx
+				 id)))
+			    internal-ids)
+		  ;; Produce result ------------------------------
+		  (with-syntax ([(defn ...) defns]
+				[(internal-id ...) internal-ids])
+		    (syntax/loc stx
+		      (let ()
+			defn ...
+			(values internal-id ...)))))))]))])))