Making a Sass mixin with optional arguments

Question

I am writing a mixin like this:

@mixin box-shadow($top, $left, $blur, $color, $inset:\"\") {
    -webkit-box-shadow:          


        

Answer 1

With sass@3.4.9 :

// declare
@mixin button( $bgcolor:blue ){
    background:$bgcolor;
}

and use without value, button will be blue

//use
.my_button{
    @include button();
}

and with value, button will be red

//use
.my_button{
    @include button( red );
}

works with hexa too