.

original commit: 67abdf44f6bdbe08726174787e50ebb5eef2cf27

collects/mzlib/etc.ss

@@ -27,6 +27,7 @@
 	   nand
 	   let+
 
+	   namespace-defined?
 	   this-expression-source-directory
 	   define-syntax-set)
   
@@ -423,6 +424,13 @@
 		  [(_ expr0 expr ...)
 		   (syntax (begin expr0 expr ... rest))])))))])))
 
+ (define (namespace-defined? n)
+   (unless (symbol? n)
+     (raise-type-error 'namespace-defined? "symbol" n))
+   (with-handlers ([exn:variable? (lambda (x) #f)])
+     (namespace-variable-binding n)
+     #t))
+
  (define-syntax (this-expression-source-directory stx)
    (syntax-case stx ()
      [(_)

collects/mzlib/string.ss

@@ -6,9 +6,8 @@
 	   read-from-string
 	   read-from-string-all
 	   expr->string
-	   newline-string
-	   string->literal-regexp-string
-	   string->literal-replace-string
+	   regexp-quote
+	   regexp-replace-quote
 	   regexp-match-exact?)
 
   (require (lib "etc.ss"))
@@ -107,10 +106,10 @@
 	(write v port)
 	s)))
   
-  (define newline-string (string #\newline))
-  
-  (define string->literal-regexp-string
+  (define regexp-quote
     (opt-lambda (s [case-sens? #t])
+      (unless (string? s)
+	(raise-type-error 'regexp-quote "string" s))
       (list->string
        (apply
 	append
@@ -125,11 +124,14 @@
 	    [else (list c)]))
 	 (string->list s))))))
 
-  (define (string->literal-replace-string s)
+  (define (regexp-replace-quote s)
+    (unless (string? s)
+      (raise-type-error 'regexp-replace-quote "string" s))
     (regexp-replace* "\\\\" s "\\\\\\\\"))
 
   (define regexp-match-exact?
     (lambda (p s)
-      (let ([m (regexp-match p s)])
+      (let ([m (regexp-match-positions p s)])
 	(and m
-	     (string=? (car m) s))))))
+	     (zero? (caar m))
+	     (= (string-length s) (cdar m)))))))