Rapid-stache

rapid-stache.js

/**
 * This doesn't pretend to be a proper, or fully-featured templating library
 * it's merely a light-weight one used for rapid prototyping.
 * Anti-Features:
 *   - no precompilation 
 *   - no fancy iteration or repeats
 *   - pretty much nothing except string replacement
 *   - basic filters
 * 
 * https://gist.github.com/pentaphobe/7955994
 **/
!function InitialiseLibrary (window) {
    var __ = window.__ || ( window.__ = {} );

    __.template = function(txt, defaults) {

        var _open = '{{';
        var _close = '}}';

        return function splitter(obj) {
            var idx = 0;
            var len = txt.length;
            var result = '';

            obj = __.extend({}, defaults, obj);

            function resetProto() {
                obj.prototype = oldProto;
            }

            while (idx < len) {
                var openIdx = txt.indexOf(_open, idx);
                if (openIdx === -1) {
                    break;
                }

                result += txt.substring(idx, openIdx);

                var closeIdx = txt.indexOf(_close, openIdx+2);
                if (closeIdx === -1) {
                    console.error('Unclosed template data - got as far as:', result);                
                    return false;
                }

                var key = txt.substring(openIdx+2, closeIdx);
                // assume the first char is '=' for now
                var cmd = key.charAt(0);
                key = key.substring(1);
                
                // parse filter pipes
                var filters = key.split('|').map( function(txt) { return txt.trim(); } )
                key = filters[0];
                filters = filters.slice(1);

                var tempResult = obj[key];
                filters.forEach( function(item, idx) {
                  tempResult = __.filter(item, tempResult);
                });
                result += tempResult;

                idx = closeIdx + 2;
            }
            if (idx < len) {
                result += txt.substring(idx);
            }
            
            return result;
        };

    };

    __.extend = function() {
        if (!arguments.length) return false;

        var obj = arguments[0];
        for (var i=1, max=arguments.length ; i < max; i++) {
            var arg = arguments[i];
            for (var key in arg) {
                if (arg.hasOwnProperty(key)) {
                    obj[key] = arg[key];
                }
            }
        }
        return obj;
    };  
    
    __.filters = {
      toUpperCase : function(txt) { return txt.toUpperCase(); },
      toLowerCase : function(txt) { return txt.toLowerCase(); }
    };
    
    /**
     * Performs a named filter on the supplied data
     */
    __.filter = function(name, data) {
      if (!__.filters[name]) return data;
      
      return __.filters[name](data);
    };

}(this);

rapid-stache_example_usage.js

/**
 * Basic usage example extracted from the original gist
 */
 
!function main() {

    tpl = 'hello {{=name}}, I am a {{=adjective | toUpperCase}} templating system';
    go = __.template(tpl, {name:'nobody', adjective:'poorly-utilised'});
    console.log(go());
    console.log(go({
        name:'john',
        adjective: 'doughy'
    }));

}();