Sass interpolate a variable name to string

Question

We were provided a number of colors with specific hover-state colors associated:

$red: #cb333b;
$red-hover: #fe666e;
$brown: #544742;
$brown-hover: #877a75;
etc.

Since all the colors are formatted the same way, so I was hoping to write a mixin that takes the color's variable name, then concatenates -hover to the end. This is my first try:

@mixin button_colorizor($color) {
  border-color: $color;
  color: $color;
  &:hover {
    color: #{$color}-hover;
    border-color: #{$color}-hover;
  }
}

But what this does is output a color like this: #f1735f-hover. The same thing when I do this: color: #{$color+-hover};

Answer 1

You can create map of colors. And get color values by its names.

Demo on sassmeister.

$colors: (
  red: #cb333b,
  red-hover: #fe666e,
  brown: #544742,
  brown-hover: #877a75
);

@mixin button_colorizor($color) {
  color: map-get($colors, $color);
  border-color: map-get($colors, $color);

  &:hover {
    color: map-get($colors, $color + '-hover');
    border-color: map-get($colors, $color + '-hover');
  }
}

a {
  @include button_colorizor(red);
}

span {
  @include button_colorizor(brown);
}

This code is compiled to css:

a {
  color: #cb333b;
  border-color: #cb333b;
}
a:hover {
  color: #fe666e;
  border-color: #fe666e;
}

span {
  color: #544742;
  border-color: #544742;
}
span:hover {
  color: #877a75;
  border-color: #877a75;
}