Passing a list to a mixin in SASS as parameters? - compass-sass

Question

I'm trying to make a SCSS stylesheet easily configurable by defining a set of constants that will be used in a number of mixins and with the Compass library. Ideally, I'd like to be able to do the following:
$item-bgs: linear-gradient(white, black), #ccc;
#mixin some-mixin() {
#include background-with-css2-fallback($item-bgs*);
}
The background-with-css2-fallback is a Compass mixin that accepts up to 10 params. I'm assuming that SASS does not currently support passing a list parameter as the argument list, otherwise Compass would probably use it, but I'm wondering if I can get the $item-bgs list to be the first 2 arguments to the background-with-css2-fallback mixin. Is there a way to do this currently, or is it even planned for SASS in the future?

Answer 1

It may not be supported by SASS natively, but Compass does support passing a list as the first argument to the background-with-css2-fallback mixin. If you look at the source for the mixin, you'll see that it uses a compact function that handles the logic for collapsing the arguments into a single list, whether passed individually or in a single list parameter.
For example, this works fine for me:
#import "compass";
$item-bgs: (linear-gradient(white, black), #ccc);
.test {
#include background-with-css2-fallback($item-bgs);
}

Answer 2

Examples of useing maps as arguments:
Example 1 (list)
#mixin transition($property...){
#if $property {
transition-property: $property;
}
#else {
transition-property: all;
}
transition-timing-function: ease-in-out;
transition-duration: .3s;
transition-delay: 0;
}
.btn {
color: black;
border: 1px solid black;
#include transition(color, border-color);
&:hover {
color: red;
border-color: red;
}
}
Example 2 (Custom params)
#use 'sass:meta';
#mixin example2($args...) {
#each $key, $value in meta.keywords($args) {
#{$key}: #{$value};
}
}
.shape {
#include example2($width:200px, $height:100px);
}
Example 3 (map)
#mixin colors($args:()) {
#if length($colors) > 0 {
#each $key, $val in $args{
.txt-#{$key} {
color: #{$value};
}
.bg-#{$key} {
background-color: #{$value};
}
}
}
}
$colors_map: (
primary: blue,
secondary: green,
accent: red,
light: white,
dark: black
);
#include colors($colors_map);