less.js/lib/less/functions/string.js

var Quoted = require("../tree/quoted"),
    Anonymous = require("../tree/anonymous"),
    JavaScript = require("../tree/javascript"),
    functionRegistry = require("./function-registry");

functionRegistry.addMultiple({
    e: function (str) {
        return new(Anonymous)(str instanceof JavaScript ? str.evaluated : str.value);
    },
    escape: function (str) {
        return new(Anonymous)(encodeURI(str.value).replace(/=/g, "%3D").replace(/:/g, "%3A").replace(/#/g, "%23").replace(/;/g, "%3B").replace(/\(/g, "%28").replace(/\)/g, "%29"));
    },
    replace: function (string, pattern, replacement, flags) {
        var result = string.value;

        result = result.replace(new RegExp(pattern.value, flags ? flags.value : ''), replacement.value);
        return new(Quoted)(string.quote || '', result, string.escaped);
    },
    '%': function (string /* arg, arg, ...*/) {
        var args = Array.prototype.slice.call(arguments, 1),
            result = string.value;

        for (var i = 0; i < args.length; i++) {
            /*jshint loopfunc:true */
            result = result.replace(/%[sda]/i, function(token) {
                var value = token.match(/s/i) ? args[i].value : args[i].toCSS();
                return token.match(/[A-Z]$/) ? encodeURIComponent(value) : value;
            });
        }
        result = result.replace(/%%/g, '%');
        return new(Quoted)(string.quote || '', result, string.escaped);
    }
});