From 669d47ce8dd9c1df1033a7f0715be76843be67a3 Mon Sep 17 00:00:00 2001
From: James deBoer <james@huronbox.com>
Date: Fri, 16 May 2014 18:14:29 -0700
Subject: [PATCH] perf(interpolate): 20%. Cache the interpolated expressions.

---
 lib/core/interpolate.dart | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/lib/core/interpolate.dart b/lib/core/interpolate.dart
index aed34f53f..8c74a2c23 100644
--- a/lib/core/interpolate.dart
+++ b/lib/core/interpolate.dart
@@ -10,6 +10,7 @@ part of angular.core_internal;
  */
 @Injectable()
 class Interpolate implements Function {
+  var _cache = {};
   /**
    * Compiles markup text into expression.
    *
@@ -23,6 +24,15 @@ class Interpolate implements Function {
 
   String call(String template, [bool mustHaveExpression = false,
               String startSymbol = '{{', String endSymbol = '}}']) {
+    if (mustHaveExpression == false && startSymbol == '{{' && endSymbol == '}}') {
+      // cachable
+      return _cache.putIfAbsent(template, () => _call(template, mustHaveExpression, startSymbol, endSymbol));
+    }
+    return _call(template, mustHaveExpression, startSymbol, endSymbol);
+  }
+
+  String _call(String template, [bool mustHaveExpression = false,
+              String startSymbol, String endSymbol]) {
     if (template == null || template.isEmpty) return "";
 
     final startLen = startSymbol.length;