From e2e8f168458cb54854e1cac58c9ab5ed238a67b5 Mon Sep 17 00:00:00 2001
From: Chris Wanstrath <chris@ozmm.org>
Date: Sun, 18 Apr 2010 10:48:54 -0400
Subject: [PATCH] Higher Order Sections

If a section key returns a function, it will be called
and passed both the unrendered block of text and a renderer
convenience function.

Given this JS:

  "name": "Tater",
  "bolder": function() {
    return function(text, render) {
      return "<b>" + render(text) + '</b>'
    }
  }

And this template:

  {{#bolder}}Hi {{name}}.{{/bolder}}

We'll get this output:

  <b>Hi Tater.</b>

As you can see, we're pre-processing the text in the block.
This can be used to implement caching, filters (like syntax
highlighting), etc.

You can use `this.name` to access the attribute `name` from
your view.
---
 CHANGES.md                          |  1 +
 README.md                           | 28 ++++++++++++++++++++++++++++
 examples/higher_order_sections.html |  1 +
 examples/higher_order_sections.js   |  9 +++++++++
 examples/higher_order_sections.txt  |  1 +
 mustache.js                         |  5 +++++
 6 files changed, 45 insertions(+)
 create mode 100644 examples/higher_order_sections.html
 create mode 100644 examples/higher_order_sections.js
 create mode 100644 examples/higher_order_sections.txt

diff --git a/CHANGES.md b/CHANGES.md
index 7134ffc..bd88ae9 100644
--- a/CHANGES.md
+++ b/CHANGES.md
@@ -1,6 +1,7 @@
 # mustache.js Changes
 
 ## 0.3.0 (??-??-????)
+* Added higher order sections.
 
 
 ## 0.2.3 (28-03-2010)
diff --git a/README.md b/README.md
index 0eea4e2..7c1e8e0 100644
--- a/README.md
+++ b/README.md
@@ -88,6 +88,34 @@ the items. Use `{{.}}` to access the current item inside the enumeration section
     Joe's shopping card: <ul><li>bananas</li><li>apples</li></ul>
 
 
+### Higher Order Sections
+
+If a section key returns a function, it will be called and passed both the unrendered
+block of text and a renderer convenience function.
+
+Given this JS:
+
+    "name": "Tater",
+    "bolder": function() {
+      return function(text, render) {
+        return "<b>" + render(text) + '</b>'
+      }
+    }
+
+And this template:
+
+    {{#bolder}}Hi {{name}}.{{/bolder}}
+
+We'll get this output:
+
+    <b>Hi Tater.</b>
+
+As you can see, we're pre-processing the text in the block. This can be used to
+implement caching, filters (like syntax highlighting), etc.
+
+You can use `this.name` to access the attribute `name` from your view.
+
+
 ### View Partials
 
 mustache.js supports a quite powerful but yet simple view partial mechanism. Use the
diff --git a/examples/higher_order_sections.html b/examples/higher_order_sections.html
new file mode 100644
index 0000000..04f5318
--- /dev/null
+++ b/examples/higher_order_sections.html
@@ -0,0 +1 @@
+{{#bolder}}Hi {{name}}.{{/bolder}}
diff --git a/examples/higher_order_sections.js b/examples/higher_order_sections.js
new file mode 100644
index 0000000..c7e558e
--- /dev/null
+++ b/examples/higher_order_sections.js
@@ -0,0 +1,9 @@
+var higher_order_sections = {
+  "name": "Tater",
+  "helper": "To tinker?",
+  "bolder": function() {
+    return function(text, render) {
+      return "<b>" + render(text) + '</b> ' + this.helper;
+    }
+  }
+}
\ No newline at end of file
diff --git a/examples/higher_order_sections.txt b/examples/higher_order_sections.txt
new file mode 100644
index 0000000..9db786a
--- /dev/null
+++ b/examples/higher_order_sections.txt
@@ -0,0 +1 @@
+<b>Hi Tater.</b> To tinker?
diff --git a/mustache.js b/mustache.js
index 3ff899c..4a73e22 100644
--- a/mustache.js
+++ b/mustache.js
@@ -109,6 +109,11 @@ var Mustache = function() {
             return that.render(content, that.merge(context,
                     that.create_context(row)), partials, true);
           }).join("");
+        } else if(typeof value === "function") {
+          // higher order section
+          return value.call(context, content, function(text) {
+            return that.render(text, context, partials, true);
+          })
         } else if(value) { // boolean section
           return that.render(content, context, partials, true);
         } else {