what is mixins in scss code example

Example 1: sass mixin

@mixin transform($property) {
  -webkit-transform: $property;
  -ms-transform: $property;
  transform: $property;
}
.box { @include transform(rotate(30deg)); }

Example 2: scss @mixin base

@mixin rtl($property, $ltr-value, $rtl-value) {
  #{$property}: $ltr-value;

  [dir=rtl] & {
    #{$property}: $rtl-value;
  }
}

.sidebar {
  @include rtl(float, left, right);
}

Example 3: Sass @mixin and @include

@mixin important-text {
  color: red;
  font-size: 25px;
  font-weight: bold;
  border: 1px solid blue;
}

Example 4: sass mixin

@mixin css-triangle($color, $direction, $size: 6px, $position: absolute, $round: false){
    @include pseudo($pos: $position);
    width: 0;
    height: 0;
    @if $round {
        border-radius: 3px;
    }
    @if $direction == down {
        border-left: $size solid transparent;
        border-right: $size solid transparent;
        border-top: $size solid $color;
        margin-top: 0 - round( $size / 2.5 );
    } @else if $direction == up {
        border-left: $size solid transparent;
        border-right: $size solid transparent;
        border-bottom: $size solid $color;
        margin-bottom: 0 - round( $size / 2.5 );
    } @else if $direction == right {
        border-top: $size solid transparent;
        border-bottom: $size solid transparent;
        border-left: $size solid $color;
        margin-right: -$size;
    } @else if  $direction == left {
        border-top: $size solid transparent;
        border-bottom: $size solid transparent;
        border-right: $size solid $color;
        margin-left: -$size;
    }
}