File Extension Change Shortcut

By  on  

Changing the extension of a file seems like something you would do often enough to know how to do it from command line.  One annoying part of moving a file is repeating the file name a second time when all I want to do is change the extension.  A minor annoyance but an annoyance nonetheless.

I recently found that you can quickly change a file's extension with this handy shortcut:

# mv filename.{old,new}
mv code.{txt,js}

The braced syntax provides a way to quickly swap out the file extension without needing to repeat the file name.  Sweet!

Recent Features

  • By
    5 HTML5 APIs You Didn’t Know Existed

    When you say or read "HTML5", you half expect exotic dancers and unicorns to walk into the room to the tune of "I'm Sexy and I Know It."  Can you blame us though?  We watched the fundamental APIs stagnate for so long that a basic feature...

  • By
    fetch API

    One of the worst kept secrets about AJAX on the web is that the underlying API for it, XMLHttpRequest, wasn't really made for what we've been using it for.  We've done well to create elegant APIs around XHR but we know we can do better.  Our effort to...

Incredible Demos

Discussion

  1. This does not only work for file extensions. You can generally use the curly braces syntax to “generate” multiple words/arguments for a bash command: http://www.gnu.org/software/bash/manual/bashref.html#Brace-Expansion

Wrap your code in <pre class="{language}"></pre> tags, link to a GitHub gist, JSFiddle fiddle, or CodePen pen to embed!