Contemplate

Light-weight, fast and flexible "object-oriented" template engine for PHP, Python, Node.js, Browser client-side and XPCOM JavaScript

Contemplate.js, Contemplate.min.js

Meaning of Yoga in Indian Philosophy (wikipedia) ("unifying through yoga, contemplate and attain mastery")

see also:

HtmlWidget html widgets used as (template) plugins and/or standalone for PHP, Python, Node.js / Browser / XPCOM Javascript both client and server-side (can be used as plugins for Contemplate)
Tao A simple, tiny, isomorphic, precise and fast template engine for handling both string and live dom based templates
ModelView a light-weight and flexible MVVM framework for JavaScript/HTML5
ModelView MVC jQueryUI Widgets plug-n-play, state-full, full-MVC widgets for jQueryUI using modelview.js (e.g calendars, datepickers, colorpickers, tables/grids, etc..) (in progress)
Importer simple class & dependency manager and loader for PHP, Python, Node.js / Browser / XPCOM Javascript
PublishSubscribe a simple and flexible publish-subscribe pattern implementation for PHP, Python, Node.js / Browser / XPCOM Javascript
Dromeo a flexible, and powerfull agnostic router for PHP, Python, Node.js / Browser / XPCOM Javascript
Dialect a simple cross-vendor & cross-platform SQL construction for PHP, Python, Node.js / Browser / XPCOM Javascript
Xpresion a simple and flexible eXpression parser engine (with custom functions and variables support) for PHP, Python, Node.js / Browser / XPCOM Javascript
GrammarTemplate versatile and intuitive grammar-based templating for PHP, Python, Node.js / Browser / XPCOM Javascript
GrammarPattern versatile grammar-based pattern-matching for Node / XPCOM / JS (IN PROGRESS)
Regex Analyzer/Composer Regular Expression Analyzer and Composer for PHP, Python, Node.js / Browser / XPCOM Javascript
DateX eXtended & localised Date parsing, diffing, formatting and validation for PHP, Python, Node.js / Browser / XPCOM Javascript
Abacus a fast combinatorics and computation library for PHP, Python, Node.js / Browser / XPCOM Javascript
RT client-side real-time communication for Node/XPCOM/JS with support for Poll / BOSH / WebSockets
Asynchronous a simple manager for async, linearised, parallelised, interleaved and sequential tasks for JavaScript

This started as a a proof-of-concept but developed into a full-blown and versatile template engine.

The original inspiration came from an old post by John Resig (http://ejohn.org/blog/javascript-micro-templating/)

Note There are a couple of other frameworks named also contemplate

http://www.arlomedia.com/software/contemplate/assembled/introduction.html
There is an older and quite different template engine for node named also "contemplate" here and here

This repository and project is completely unrelated to these frameworks.

If you use Contemplate in your application and you want to share it, feel free to submit an example link

Rationale

There are many templating engines out there, which are elegant, fast, multipurpose and so on.. Most of the sophisticated engines use a custom parser (and usually a full-fledged framework) to build the engine.

This is highly versatile:

but can have performance issues sometimes
and / or requires to learn a (completely) new syntax for building a template.

These drawbacks can be compensated if one uses PHP itself as templating engine. PHP already IS a templating language and a very fast at it.

This can create very simple, intuitive and fast templates.

The drawbacks of this approach are:

It works only with PHP, and many times the same template needs to be used also by JavaScript
It can be cumbersome to combine or iterate over templates and parts.

Contemplate seeks to find the best balance between these requirements.

The solution is inspired by John Resig's post (see above) and the fact that PHP, Python and JavaScript share a common language subset.

Features:

Contemplate does a minimum parsing (and caching) in order to create dynamic templates and trying to contain the needed functionality inside the common language subset(s).
Most of the time this can be accomplished, the rest functionality is built with custom functions which mostly resemble the PHP syntax, yet work the same in all the engine's implementations.
Uniform functionality, Engine Implementations for PHP , Python , Node.js , XPCOM and Browser client-side JavaScript (NOTE javascript engine supports both sync and async operations both callback-based and promise-based)
Simple and light-weight ( only one relatively small class for each implementation, no other dependencies ) ~50kB minified, ~16kB zipped
Fast , can cache templates dynamically (filesystem caching has 3 modes, NONE which uses only in-memory caching, NOUPDATE which caches the templates only once and AUTOUPDATE which re-creates the cached template if original template has changed, useful for debugging)
Generated cached template code is formatted and annotated with comments, for easy debugging (note: javascript cached templates are UMD modules which can be used in both node.js/AMD/XPCOM/browser/es6 module fallback)
Syntax close to PHP (there was an effort to keep the engine syntax as close to PHP syntax as possible, to avoid learning another language syntax)
Easily extensible , configurable
Object-oriented , templates implement inheritance and polymorphism in a full object-oriented manner (see below)
Supports multiple dynamic contexts , and contextual settings so that different modules of an application can use the engine independantly (see examples and manual)
Localization , Pluralisation , Date formatting built-in and configurable easily ( simple Data escaping is also supported)
X-GetText / POEdit translation-friendly localisation (keywords: locale, xlocale:1,2c, nlocale:2, nlocale:3, nxlocale:2,4c, nxlocale:3,4c)
Date manipulation similar to PHP format (ie date function). An extended, localized version of php's date function ldate is also implemented in the framework
Loops can have optional elsefor statement when no data, or data is empty (see tests)
Templates can include other templates (similar to PHP include directive), these includes wil be compiled into the the template that called them
Templates can call another template using tpl function, these templates are called as templates subroutines and parsed by themselves
Templates and template functions can also have inline templates as parameters via inline template function
Template Inheritance , templates can extend/inherit other templates using extends directive and override blocks using block , endblock directives (see examples)
Direct Super reference , templates can use the super template function to directly reference (and call) a super block if needed in OO manner (see examples)
Nested Blocks , template blocks can be nested and repeated in multiple ways (see examples)
Custom Plugins , can be used as template functions to enhance/extend the engine functionality (see examples)
custom plugins can be also inlined, i.e their code can be expanded at compile-time using Contemplate::inline templates in their definition, e.g saving unnecessary look-ups at render-time (see examples)

Dependencies

Only 3 classes are used (Contemplate.php, Contemplate.js, Contemplate.py), no other dependencies
PHP 5.2+ supported
Node 0.8+ supported
Python 2.x or 3.x supported
all browsers
Contemplate is also a XPCOM JavaScript Component (Firefox) (e.g to be used in firefox browser addons/plugins for templating)

Todo

add support for multiple contexts (which include separate templates, cache directories and related parameters) so that the engine can be used in same application by different modules independantly [DONE]
simplify template directives, functions and plugins notation by eliminating the % prefix (compatibility mode to older versions also supported) [DONE]
support asynchronous template loading/parsing/rendering/writing for node/browser [DONE]
add Contemplate implementations for ActionScript, Perl, Java, Scala [TODO?]
transform Contemplate (for PHP) into a PHP C-extension, Contemplate (for node) into standalone executable (eg. https://github.com/crcn/nexe) [TODO?]
keep-up with php, node, python, browsers updates

Performance

(for php see /tests/perf/perf.php)

Note: The engines included in the (following) tests, have different philosophy and in general provide different features. These are only illustrative modulo all the other features.

Render Time

The following tests were made on a revision of a 2013 jsperf test for resig micro-templating, handlebars, contemplate, mustache, underscore, doT and kendoui template engines. More tests should be done.

Contemplate (0.6.5) was 2nd place on Firefox and 3rd (or close) place on Opera, IE, while Contemplate was average to slower on Chrome. The reason was mostly that Contemplate was using a code to copy/isolate the input data every time inside the render function, which most of the time is redundant, else user can use the Contemplate.data method to create a shallow copy suitable to be used as render data. So this was removed, plus some minor refactoring and minor loop optimisation.

This resulted in great performance increase as shown below. (see changelog)

Previous tests are here jsperf/0.6.5, jsperf/0.6.7, jsperf/0.7, jsperf/0.7.1, jsperf/0.8, jsperf/0.8.1, jsperf/1.0.0, jsperf/1.0.0 (1.0.0+ format)

Contemplate (1.0.0) is (consistently) near 1st place on all browsers.