Add an escape sequence to avoid polymer to bind the content of curly/…

…square brackets.

Usage:

{{test}}: normal behaviour
{{\test}}: don't bind to test and print {{test}}
{{\\test}}: don't bind to test and print {{\test}}

[[test]]: normal behaviour
[[\test]]: don't bind to test and print [[test]]
[[\\test]]: don't bind to test and print [[\test]]

src/lib/annotations/annotations.html

@@ -101,7 +101,7 @@
                                     '(?:' + ARGUMENTS + '?' + ')' +
                                   '\\)\\s*' + ')';
       var BINDING = '(' + IDENT + '\\s*' + ARGUMENT_LIST + '?' + ')'; // Group 3
-      var OPEN_BRACKET = '(\\[\\[|{{)' + '\\s*';
+      var OPEN_BRACKET = '(\\[\\[\\\\*|{{\\\\*)' + '\\s*';
       var CLOSE_BRACKET = '(?:]]|}})';
       var NEGATE = '(?:(!)\\s*)?'; // Group 2
       var EXPRESSION = OPEN_BRACKET + NEGATE + BINDING + CLOSE_BRACKET;
@@ -123,31 +123,48 @@
       // m[1]: '{{'          '[['
       // m[2]: ''            '!'
       // m[3]: 'prop'        'compute(foo,bar)'
+      // Example: "literal1{{\prop}}literal2[[\!compute(foo,bar)]]final"
+      // Regex matches:
+      //        Iteration 1:  Iteration 2:
+      // m[1]: '{{\'          '[[\'
+      // m[2]: ''            '!'
+      // m[3]: 'prop'        'compute(foo,bar)'
       while ((m = re.exec(text)) !== null) {
         // Add literal part
         if (m.index > lastIndex) {
           parts.push({literal: text.slice(lastIndex, m.index)});
         }
-        // Add binding part
-        // Mode (one-way or two)
-        var mode = m[1][0];
-        var negate = Boolean(m[2]);
-        var value = m[3].trim();
-        var customEvent, notifyEvent, colon;
-        if (mode == '{' && (colon = value.indexOf('::')) > 0) {
-          notifyEvent = value.substring(colon + 2);
-          value = value.substring(0, colon);
-          customEvent = true;
+        // Check if the expression inside brackets must be treated as literal
+        var treatAsLiteral = m[1][2] === '\\';
+        if (!treatAsLiteral) {
+          // Add binding part
+          // Mode (one-way or two)
+          var mode = m[1][0];
+          var negate = Boolean(m[2]);
+          var value = m[3].trim();
+          var customEvent, notifyEvent, colon;
+          if (mode == '{' && (colon = value.indexOf('::')) > 0) {
+            notifyEvent = value.substring(colon + 2);
+            value = value.substring(0, colon);
+            customEvent = true;
+          }
+          parts.push({
+            compoundIndex: parts.length,
+            value: value,
+            mode: mode,
+            negate: negate,
+            event: notifyEvent,
+            customEvent: customEvent
+          });
+          lastIndex = re.lastIndex;
+        } else {
+          // Add expression as literal
+          var literalExpression = text.slice(m.index, re.lastIndex);
+          // Remove a slash
+          literalExpression = literalExpression.slice(0, 2) + literalExpression.slice(3);
+          parts.push({literal: literalExpression});
+          lastIndex = re.lastIndex;
         }
-        parts.push({
-          compoundIndex: parts.length,
-          value: value,
-          mode: mode,
-          negate: negate,
-          event: notifyEvent,
-          customEvent: customEvent
-        });
-        lastIndex = re.lastIndex;
       }
       // Add a final literal part
       if (lastIndex && lastIndex < text.length) {