Initial release 2009 (2009) Website mustache.github.io | License MIT | |
Mustache is a simple web template system with implementations available for ActionScript, C++, Clojure, CoffeeScript, ColdFusion, Common Lisp, D, Delphi, Erlang, Fantom, Go, Haskell, Io, Java, JavaScript, Julia, Lua, .NET, Objective-C, Perl, PHP, Pharo, Python, Racket, Ruby, Rust, Scala, Swift, CFEngine and XQuery.
Contents
- History and principles
- Examples
- Technical details
- Specification and implementations
- Variations and Derivatives
- Handlebars
- References
Mustache is described as a "logic-less" system because it lacks any explicit control flow statements, like if and else conditionals or for loops; however, both looping and conditional evaluation can be achieved using section tags processing lists and lambdas.
It is named "Mustache" because of heavy use of curly braces ,{ }, that resemble a sideways moustache.
Mustache is used mainly for mobile and web applications.
History and principles
Mustache-1 was inspired by ctemplate and et, and started as a GitHub distribution at the end of 2009. A first version of the template engine was implemented with Ruby, running YAML template texts. The (preserved) main principles were:
The input data can be a class, so input data can be characterized as an MVC-view. The Mustache template does nothing but reference methods in the (input data) view. All the logic, decisions, and code is contained in this view, and all the markup (ex. output XML) is contained in the template. In an MVP context: input data is from MVP-presenter, and the Mustache template is the MVP-view.
Examples
The simplest template:
Template with section tag:
Here, when x is a Boolean value then the section tag acts like an if conditional, but when x is an array then it acts like a foreach loop.
Template that is not escaped:
Here, if body contains HTML, it won't be escaped.
Technical details
Syntax highlighting is available in Vim, Emacs, TextMate, Coda and Atom.
The Mustache templates support is built into many web application frameworks (ex. CakePHP). The support in JavaScript includes both client-side programming with many popular JavaScript libraries and Ajax frameworks like jQuery, Dojo and YUI, as well as server-side JavaScript using Node.js and CommonJS.
Specification and implementations
There are many Mustache Engine implementations available, and all of them meet a common specification (see external links) — that for final users results in the common syntax.
As of March 2011, the last SPEC_VERSION was 1.1.2.
All Mustache Engines, in the v1.X architecture, have a render method, a Mustache_Compiler class and a Parser class.
Variations and Derivatives
Mustache inspired numerous JavaScript template libraries which forked from the original simplicity to add certain functionality or use. Particularly notable,
Handlebars
Handlebars.js is self-described as:
Handlebars.js is an extension to the Mustache templating language created by Chris Wanstrath. Handlebars.js and Mustache are both logicless templating languages that keep the view and the code separated like we all know they should be.
Handlebars is currently one of the most popular GitHub/NPM packages with (as of this date) over 5.3 Million downloads in the last month. (Which surpasses the popularity of even Mustache (at 824K downloads last month) or more often discussed libraries such as: Angular.js (620K), React (2.6M) or Backbone.js (615K). While NPM downloads is an important metric to determine popularity and with it likelihood of better documentation, issue resolution, community support and advancement of new features, popularity among packages fluctuates month to month and certainly annually and downloads do not necessarily imply more usage, especially if Yarn downloads don't count.)
Handlebars differs from its predecessor in that:
Using the context:
Where as the same in Mustache would require either a block of that nested object or flattening context and thus would be:
And a few other functionalities mostly related to making usage easier.