Change the definition of substring-lower-case? and

substring-upper-case? so that strings with no upper (lower) case
characters match.  The previous definition required at least one lower
(upper) case character.  Thus the empty string (or a string with only
non-alphabetic characters) is both lower and upper case, while it was
previously neither.

diff --git a/v7/src/runtime/string.scm b/v7/src/runtime/string.scm
index aeb576a65a68b3879d911650aa82773dc20764af..6bfefd28cafe5d3b8833ce8d451e550a6c79a149 100644 (file)
--- a/v7/src/runtime/string.scm
+++ b/v7/src/runtime/string.scm
@@ -1,6 +1,6 @@
 #| -*-Scheme-*-
 
-$Header: /Users/cph/tmp/foo/mit-scheme/mit-scheme/v7/src/runtime/string.scm,v 14.5 1992/08/28 16:05:58 jinx Exp $
+$Id: string.scm,v 14.6 1992/12/01 14:52:03 gjr Exp $
 
 Copyright (c) 1988-1992 Massachusetts Institute of Technology
 
@@ -237,15 +237,15 @@ MIT in each case. |#
 
 (define (substring-upper-case? string start end)
   (let find-upper ((start start))
-    (and (fix:< start end)
-        (let ((char (string-ref string start)))
-          (if (char-upper-case? char)
-              (let search-rest ((start (fix:+ start 1)))
-                (or (fix:= start end)
-                    (and (not (char-lower-case? (string-ref string start)))
-                         (search-rest (fix:+ start 1)))))
-              (and (not (char-lower-case? char))
-                   (find-upper (fix:+ start 1))))))))
+    (or (not (fix:< start end))
+       (let ((char (string-ref string start)))
+         (if (char-upper-case? char)
+             (let search-rest ((start (fix:+ start 1)))
+               (or (fix:= start end)
+                   (and (not (char-lower-case? (string-ref string start)))
+                        (search-rest (fix:+ start 1)))))
+             (and (not (char-lower-case? char))
+                  (find-upper (fix:+ start 1))))))))
 
 (define (string-upcase string)
   (let ((string (string-copy string)))
@@ -260,15 +260,15 @@ MIT in each case. |#
 
 (define (substring-lower-case? string start end)
   (let find-lower ((start start))
-    (and (fix:< start end)
-        (let ((char (string-ref string start)))
-          (if (char-lower-case? char)
-              (let search-rest ((start (fix:+ start 1)))
-                (or (fix:= start end)
-                    (and (not (char-upper-case? (string-ref string start)))
-                         (search-rest (fix:+ start 1)))))
-              (and (not (char-upper-case? char))
-                   (find-lower (fix:+ start 1))))))))
+    (or (not (fix:< start end))
+       (let ((char (string-ref string start)))
+         (if (char-lower-case? char)
+             (let search-rest ((start (fix:+ start 1)))
+               (or (fix:= start end)
+                   (and (not (char-upper-case? (string-ref string start)))
+                        (search-rest (fix:+ start 1)))))
+             (and (not (char-upper-case? char))
+                  (find-lower (fix:+ start 1))))))))
 
 (define (string-downcase string)
   (let ((string (string-copy string)))