ionic-framework/src/themes/ionic.mixins.scss

// Appearance
// --------------------------------------------------

@mixin appearance($val) {
  -moz-appearance: $val;
  -ms-appearance: $val;
  -webkit-appearance: $val;
  appearance: $val;
}


// Input Placeholder
// --------------------------------------------------

@mixin placeholder($color: #999, $text-indent: 0) {
  &::-moz-placeholder { // Firefox 19+
    color: $color;
  }

  &:-ms-input-placeholder {
    color: $color;
  }

  &::-webkit-input-placeholder {
    // Safari placeholder margin issue
    text-indent: $text-indent;
    color: $color;
  }
}


// SVG Background Image Mixin
// --------------------------------------------------

@mixin svg-background-image($svg) {
  $url: url-encode($svg);
  background-image: url("data:image/svg+xml;charset=utf-8,#{$url}");
}

// Check that the given map values are in ascending order
// ---------------------------------------------------------------------------------

@mixin assert-ascending($map, $map-name) {
  $prev-key: null;
  $prev-num: null;
  @each $key, $num in $map {
    @if $prev-num == null {
      // Do nothing
    } @else if not comparable($prev-num, $num) {
      @warn "Potentially invalid value for #{$map-name}: This map must be in ascending order, but key '#{$key}' has value #{$num} whose unit makes it incomparable to #{$prev-num}, the value of the previous key '#{$prev-key}' !";
    } @else if $prev-num >= $num {
      @warn "Invalid value for #{$map-name}: This map must be in ascending order, but key '#{$key}' has value #{$num} which isn't greater than #{$prev-num}, the value of the previous key '#{$prev-key}' !";
    }
    $prev-key: $key;
    $prev-num: $num;
  }
}

// Check that the first value in the given map starts at 0
// ---------------------------------------------------------------------------------

@mixin assert-starts-at-zero($map, $map-name) {
  $values: map-values($map);
  $first-value: nth($values, 1);
  @if $first-value != 0 {
    @warn "First value in `#{$map-name}` must start at 0, but starts at #{$first-value}.";
  }
}