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

Old question, I know, but I think this is still relevant. Arguably, a clearer way of doing this is to use the unquote() function (which SASS has had since version 3.0.0):

@mixin box-shadow($top, $left, $blur, $color, $inset:"") {
  -webkit-box-shadow: $top $left $blur $color unquote($inset);
  -moz-box-shadow: $top $left $blur $color unquote($inset);
  box-shadow: $top $left $blur $color unquote($inset);
}

This is roughly equivalent to Josh's answer, but I think the explicitly named function is less obfuscated than the string interpolation syntax.