several fixes on unit tests and implementation

1 files changed, 3 insertions, 3 deletions

diff --git a/lib/js/urweb.js b/lib/js/urweb.js
index f81f05e3..de1a2ad0 100644
--- a/lib/js/urweb.js
+++ b/lib/js/urweb.js
@@ -27,8 +27,8 @@ function le(x, y) { return x <= y; }
 
 // Characters
 
-function isLower(c) { return c >= 'a' && c <= 'z'; }
-function isUpper(c) { return c >= 'A' && c <= 'Z'; }
+function isLower(c) { return c.toLowerCase() == c && c != c.toUpperCase(); }
+function isUpper(c) { return c.toUpperCase() == c && c != c.toLowerCase(); }
 function isAlpha(c) { return isLower(c) || isUpper(c); }
 function isDigit(c) { return c >= '0' && c <= '9'; }
 function isAlnum(c) { return isAlpha(c) || isDigit(c); }
@@ -36,7 +36,7 @@ function isBlank(c) { return c == ' ' || c == '\t'; }
 function isSpace(c) { return isBlank(c) || c == '\r' || c == '\n'; }
 function isXdigit(c) { return isDigit(c) || (c >= 'a' && c <= 'f') || (c >= 'A' && c <= 'F'); }
 function ord(c) { return c.charCodeAt(0); }
-function isPrint(c) { return ord(c) > 31 && ord(c) < 127; }
+function isPrint(c) { return ord(c) > 31 && ord(c) != 127; }
 function toLower(c) { return c.toLowerCase(); }
 function toUpper(c) { return c.toUpperCase(); }