Perf: md unescaping opt

lib/rules_inline/escape.js

@@ -1,10 +1,13 @@
 // Proceess escaped chars and hardbreaks
 
-var ESCAPED = {};
+var ESCAPED = [];
+
+for (var i = 0; i < 256; i++) { ESCAPED.push(false); }
 
 '\\!"#$%&\'()*+,./:;<=>?@[]^_`{|}~-'
   .split('').forEach(function(ch) { ESCAPED[ch.charCodeAt(0)] = true; });
 
+
 module.exports = function escape(state, silent) {
   var ch, pos = state.pos, max = state.posMax;
 
@@ -15,7 +18,7 @@ module.exports = function escape(state, silent) {
   if (pos < max) {
     ch = state.src.charCodeAt(pos);
 
-    if (typeof ESCAPED[ch] !== 'undefined') {
+    if (ch < 256 && ESCAPED[ch] !== 0) {
       if (!silent) { state.pending += state.src[pos]; }
       state.pos += 2;
       return true;