function trimmedLeftIndex(string) {
    var index = -1,
        length = string.length;

    while (++index < length && isSpace(string.charCodeAt(index))) {}
    return index;
  }
Create a new pristine `lodash` function using the given `context` object.

@static
@memberOf _
@category Utility
@param {Object} [context=root] The context object.
@returns {Function} Returns a new `lodash` function.
@example

_.mixin({ 'foo': _.constant('foo') });

var lodash = _.runInContext();
lodash.mixin({ 'bar': lodash.constant('bar') });

_.isFunction(_.foo);
// => true
_.isFunction(_.bar);
// => false

lodash.isFunction(lodash.foo);
// => false
lodash.isFunction(lodash.bar);
// => true

// using `context` to mock `Date#getTime` use in `_.now`
var mock = _.runInContext({
  'Date': function() {
    return { 'getTime': getTimeMock };
  }
});

// or creating a suped-up `defer` in Node.js
var defer = _.runInContext({ 'setTimeout': setImmediate }).defer;