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
    JavaScript Promise API

    While synchronous code is easier to follow and debug, async is generally better for performance and flexibility. Why "hold up the show" when you can trigger numerous requests at once and then handle them when each is ready?  Promises are becoming a big part of the JavaScript world...

  • By
    Camera and Video Control with HTML5

    Client-side APIs on mobile and desktop devices are quickly providing the same APIs.  Of course our mobile devices got access to some of these APIs first, but those APIs are slowly making their way to the desktop.  One of those APIs is the getUserMedia API...

Incredible Demos

  • By
    CSS Kwicks

    One of the effects that made me excited about client side and JavaScript was the Kwicks effect.  Take a list of items and react to them accordingly when hovered.  Simple, sweet.  The effect was originally created with JavaScript but come five years later, our...

  • By
    Table Cell and Position Absolute

    If you follow me on Twitter, you saw me rage about trying to make position: absolute work within a TD element or display: table-cell element.  Chrome?  Check.  Internet Explorer?  Check.  Firefox?  Ugh, FML.  I tinkered in the console...and cussed.  I did some researched...and I...

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!