links.sass

links.sass

=style-link($link-color: blue, $visited-color: purple, $hover-color: red)
  &:link
    color: $link-color
    text-decoration: underline
  &:visited
    color: $visited-color
  &:hover
    color: $hover-color
    text-decoration: none

a
  +style-link

a.alt
  +style-link(red)

links.scss

@mixin style-link($link-color: blue, $visited-color: purple, $hover-color: red) {
  &:link { color: $link-color; text-decoration: underline; }
  &:visited { color: $visited-color; }
  &:hover { color: $hover-color; text-decoration: none; }
}

a { @include style-link; }

a.alt { @include style-link(red); }

ouput.css

a:link { color: blue; text-decoration: underline; }
a:visited { color: purple; }
a:hover { color: red; text-decoration: none; }

a.alt:link { color: red; text-decoration: underline; }
a.alt:visited { color: purple; }
a.alt:hover { color: red; text-decoration: none; }