Match IRC-style mentions at beginning of message

Author: rdb

lib/bot.js

@@ -476,7 +476,9 @@ class Bot {
       if (user) return user;
 
       return match;
-    }).replace(/@([^\s]+)/g, (match, reference) => {
+    }).replace(/^([^@\s:,]+)[:,]|@([^\s]+)/g, (match, startRef, atRef) => {
+      const reference = startRef || atRef;
+
       // this preliminary stuff is ultimately unnecessary
       // but might save time over later more complicated calculations
       // @nickname => mention, case insensitively