strsindex

1 files changed, 25 insertions, 7 deletions

diff --git a/lib/js/urweb.js b/lib/js/urweb.js
index e28446e3..2b34f8dd 100644
--- a/lib/js/urweb.js
+++ b/lib/js/urweb.js
@@ -1462,23 +1462,41 @@ 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 Array.from(s)[i].codePointAt(0); }
+function sub(s, i) { return Array.from(s)[i]; }
 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);
+    var r = Array.from(s).indexOf(ch);
     if (r == -1)
         return null;
     else
         return r;
 }
 function ssidx(h, n) {
-    var r = h.indexOf(n);
-    if (r == -1)
-        return null;
-    else
-        return r;
+    if (n == "") return 0;
+    var ah = Array.from(h);
+    var an = Array.from(n);
+    var i = 0, y = 0;
+    var top = ah.length - an.length + 1;
+    if (top < 0) top = 0;
+    var found = true;
+    
+    for(i = 0; i < top; ++i) {
+	found = true;
+	
+	for (y = 0; y < an.length; ++y) {
+	    if (ah[i + y] != an[y]) {
+		found = false;
+		break;
+	    }		
+	}
+
+	if (found)
+	    return i;
+    }
+    return null;
 }
+
 function sspn(s, chs) {
     for (var i = 0; i < s.length; ++i)
         if (chs.indexOf(s.charAt(i)) != -1)