1 files changed, 7 insertions, 7 deletions
diff --git a/lib/js/urweb.js b/lib/js/urweb.js
index c7725e28..e28446e3 100644
--- a/lib/js/urweb.js
+++ b/lib/js/urweb.js
@@ -1462,9 +1462,9 @@ function s2b(s) { return s == "True" ? true : s == "False" ? false : null; }
 function s2be(s) { return s == "True" ? true : s == "False" ? false : er("Illegal Boolean " ^ s); }
 
 function id(x) { return x; }
-function sub(s, i) { return s.charAt(i); }
-function suf(s, i) { return s.substring(i); }
-function slen(s) { return s.length; }
+function sub(s, i) { return Array.from(s)[i].codePointAt(0); }
+function suf(s, i) { return Array.from(s).slice(i).join(""); }
+function slen(s) { return Array.from(s).length; }
 function sidx(s, ch) {
     var r = s.indexOf(ch);
     if (r == -1)
@@ -1494,10 +1494,10 @@ function schr(s, ch) {
         return s.substring(r);
 }
 function ssub(s, start, len) {
-    return s.substring(start, start+len);
+    return Array.from(s).slice(start, start+len).join("");
 }
 function strlenGe(s, len) {
-    return s.length >= len;
+    return slen(s) >= len;
 }
 
 function trimZeroes(s) {
@@ -1596,11 +1596,11 @@ function strcmp(str1, str2) {
 }
 
 function chr(n) {
-    return String.fromCharCode(n);
+    return String.fromCodePoint(n);
 }
 
 function htmlifySpecialChar(ch) {
-    return "&#" + ch.charCodeAt(0) + ";";
+    return "&#" + ch.codePointAt(0) + ";";
 }