[feature] add support for optional XML and HTML pretags

lib/parse.js

@@ -15,16 +15,28 @@ var NO_ENDING_TAG = ['br', 'col', 'link', 'hr', 'command',
 //  that attr.end is relative to attr.start, reduce calculations
 function parse(content) {
 
-  // skip doctype
-  var doctype = content.indexOf('<!'),
-      begin = content.indexOf('<', doctype + 1),
-      end = content.lastIndexOf('>');
+  // Search for XML declaration and DOCTYPE declaration
+  // Both are optional
+  var begin = content.indexOf('<');
+
+  // Is XML declaration
+  if (content[begin + 1] === '?') {
+    begin = content.indexOf('<', begin + 1);
+  }
+
+  // Is DOCTYPE declartion
+  if (content[begin + 1] === '!') {
+    begin = content.indexOf('<', begin + 1);
+  }
+
+  // Find end of document
+  var end = content.lastIndexOf('>');
 
   var root = {
     isRoot: true,
     pos: {
       beforebegin: 0,
-      afterbegin: begin - 0,
+      afterbegin: begin,
       beforeend: end,
       afterend: (content.length - 1) - end
     },