Is it possible to overload mixins in sass?

Question

Let say you have a mixin for shadow like such:

@mixin box-shadow($offset, $blur, $color) {    -moz-box-shadow: $offset $offset $blur $color;    -webkit-box-shadow: $offset $offset $blur $color;    box-shadow: $offset $offset $blur $color; } 

Is it possible to overload that mixin with something like:

@mixin box-shadow($offset, $blur) {     @include box-shadow($offset, $blur, #999); } 

Or do I have to use different names for the mixins?

Answer 1

You can't overload, but the typical practice would be to set defaults.

 /* this would take color as an arg, or fall back to #999 on a 2 arg call */  @mixin box-shadow($offset, $blur, $color: #999) {    -webkit-box-shadow: $offset $offset $blur $color;    -moz-box-shadow: $offset $offset $blur $color;    box-shadow: $offset $offset $blur $color;  } 

Answer 2

If you need to tweak a vendor mixin slightly you can copy it to another file - included after the original - and edit it in there, and the vendor's original will be ignored.

@import "_their-mixins"; @import "_our-mixins"; 

Warning - this may depend on which processor you are using. At time of writing it works great using grunt and grunt-contrib-compass