raptor/lib/raptor/ecma/es6/es6.js

RaptorJS provides an AMD module loader that works in Node, Rhino and the web browser. It also includes various sub-modules to support building optimized web applications.

(function() {
    var stringProto = String.prototype;
    
    if (!stringProto.startsWith) {
        stringProto.startsWith = function(prefix, position) {
            var str = this;
            
            if (position) {
                str = str.substring(position);
            }
            
            if (str.length < prefix.length) {
                return false;
            }
            
            return str.substring(0, prefix.length) == prefix;
        };
    }
    
    if (!stringProto.endsWith) {
        stringProto.endsWith = function(suffix, position) {
            var str = this;
            
            if (position) {
                str = str.substring(position);
            }
            
            if (str.length < suffix.length) {
                return false;
            }
            
            return str.slice(0 - suffix.length) == suffix;
        };
    }
}());