He could also use \d for digit characters: /new Date\(\d+\)/g
I use the offline version of this, http://www.regexr.com/, whenever I have to work with RegExp. The online version seems pretty nice as well. Here is the saved version of the above RegEx, http://regexr.com/39lo3. For 0 or more digits use: /new Date\(\d*\)/g
