From 2055d745db5ee91e99476e837754d9bc052c3ab7 Mon Sep 17 00:00:00 2001
From: Brad Dunbar <dunbarb2@gmail.com>
Date: Fri, 23 Mar 2012 12:52:50 -0400
Subject: [PATCH 1/2] Attach template source to returned function.

---
 underscore.js | 28 +++++++++++++++-------------
 1 file changed, 15 insertions(+), 13 deletions(-)

diff --git a/underscore.js b/underscore.js
index aeaa8b1b0..1649df208 100644
--- a/underscore.js
+++ b/underscore.js
@@ -938,28 +938,30 @@
   // Underscore templating handles arbitrary delimiters, preserves whitespace,
   // and correctly escapes quotes within interpolated code.
   _.template = function(str, data) {
-    var c  = _.templateSettings;
-    var tmpl = 'var __p=[],print=function(){__p.push.apply(__p,arguments);};' +
+    var settings  = _.templateSettings;
+    var source = 'var __p=[],print=function(){__p.push.apply(__p,arguments);};' +
       'with(obj||{}){__p.push(\'' +
       str
         .replace(escaper, function(match) {
           return '\\' + escapes[match];
         })
-        .replace(c.escape || noMatch, function(match, code) {
-          return "',_.escape(" + unescape(code) + "),\n'";
+        .replace(settings.escape || noMatch, function(match, code) {
+          return "',\n_.escape(" + unescape(code) + "),\n'";
         })
-        .replace(c.interpolate || noMatch, function(match, code) {
-          return "'," + unescape(code) + ",\n'";
+        .replace(settings.interpolate || noMatch, function(match, code) {
+          return "',\n" + unescape(code) + ",\n'";
         })
-        .replace(c.evaluate || noMatch, function(match, code) {
-          return "');" + unescape(code) + ";\n__p.push('";
+        .replace(settings.evaluate || noMatch, function(match, code) {
+          return "');\n" + unescape(code) + "\n;__p.push('";
         })
-        + "');}return __p.join('');";
-    var func = new Function('obj', '_', tmpl);
-    if (data) return func(data, _);
-    return function(data) {
-      return func.call(this, data, _);
+        + "');\n}\nreturn __p.join('');";
+    var render = new Function('obj', '_', source);
+    if (data) return render(data, _);
+    var template = function(data) {
+      return render.call(this, data, _);
     };
+    template.source = 'function(obj, _){\n' + source + '\n}';
+    return template;
   };
 
   // Add a "chain" function, which will delegate to the wrapper.

From 2c0ccf03ef1b5d0d54b267341f57fd7f8161b75c Mon Sep 17 00:00:00 2001
From: Brad Dunbar <dunbarb2@gmail.com>
Date: Mon, 26 Mar 2012 13:37:06 -0400
Subject: [PATCH 2/2] Documentation for `_.template(...).source`.

---
 index.html    | 14 +++++++++++++-
 underscore.js |  2 +-
 2 files changed, 14 insertions(+), 2 deletions(-)

diff --git a/index.html b/index.html
index 9b163c16b..99453e2ce 100644
--- a/index.html
+++ b/index.html
@@ -1327,7 +1327,7 @@ _.result(object, 'stuff');
         <br />
         Compiles JavaScript templates into functions that can be evaluated
         for rendering. Useful for rendering complicated bits of HTML from JSON
-        data sources. Template functions can both interpolate variables, using<br />
+        data sources. Template functions can both interpolate variables, using
         <tt>&lt;%= &hellip; %&gt;</tt>, as well as execute arbitrary JavaScript code, with
         <tt>&lt;% &hellip; %&gt;</tt>. If you wish to interpolate a value, and have
         it be HTML-escaped, use <tt>&lt;%- &hellip; %&gt;</tt> When you evaluate a template function, pass in a
@@ -1381,6 +1381,18 @@ var template = _.template("Hello {{ name }}!");
 template({name : "Mustache"});
 =&gt; "Hello Mustache!"</pre>
 
+      <p>
+        Precompiling your templates can be a big help when debugging errors you can't
+        reproduce.  This is because precompiled templates can provide line numbers and
+        a stack trace, something that is not possible when compiling templates on the client.
+        <b>template</b> provides the <b>source</b> property on the compiled template
+        function for easy precompilation.
+      </p>
+
+      <pre>&lt;script&gt;
+  JST.project = <%= _.template(jstText).source %>;
+&lt;/script&gt;</pre>
+
 
       <h2 id="chaining">Chaining</h2>
 
diff --git a/underscore.js b/underscore.js
index 1649df208..44226a07c 100644
--- a/underscore.js
+++ b/underscore.js
@@ -960,7 +960,7 @@
     var template = function(data) {
       return render.call(this, data, _);
     };
-    template.source = 'function(obj, _){\n' + source + '\n}';
+    template.source = 'function(obj){\n' + source + '\n}';
     return template;
   };