1 files changed, 3 insertions, 0 deletions
diff --git a/lib/js/urweb.js b/lib/js/urweb.js
index c031678a..2b4d2643 100644
--- a/lib/js/urweb.js
+++ b/lib/js/urweb.js
@@ -351,6 +351,9 @@ function eh(x) {
 function ts(x) { return x.toString() }
 function bs(b) { return (b ? "True" : "False") }
 
+function sub(x, i) { return x[i]; }
+function suf(x, i) { return x.substring(i); }
+
 function pi(s) {
   var r = parseInt(s);
   if (r.toString() == s)