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Bootstrap/scss/_functions.scss

103 lines
3.2 KiB
SCSS

// Bootstrap functions
//
// Utility mixins and functions for evaluating source code across our variables, maps, and mixins.
// Ascending
// Used to evaluate Sass maps like our grid breakpoints.
@mixin _assert-ascending($map, $map-name) {
$prev-key: null;
$prev-num: null;
@each $key, $num in $map {
@if $prev-num == null or unit($num) == "%" or unit($prev-num) == "%" {
// Do nothing
} @else if not comparable($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: $num;
}
}
// Starts at zero
// Used to ensure the min-width of the lowest breakpoint starts at 0.
@mixin _assert-starts-at-zero($map, $map-name: "$grid-breakpoints") {
$values: map-values($map);
$first-value: nth($values, 1);
@if $first-value != 0 {
@warn "First breakpoint in #{$map-name} must start at 0, but starts at #{$first-value}.";
}
}
// Internal Bootstrap function to turn maps into its negative variant.
// It prefixes the keys with `n` and makes the value negative.
@function negativify-map($map) {
$result: ();
@each $key, $value in $map {
@if $key != 0 {
$result: map-merge($result, ("n" + $key: (-$value)));
}
}
@return $result;
}
// Get multiple keys from a sass map
@function map-get-multiple($map, $values) {
$result: ();
@each $key, $value in $map {
@if (index($values, $key) != null) {
$result: map-merge($result, ($key: $value));
}
}
@return $result;
}
// Replace `$search` with `$replace` in `$string`
// Used on our SVG icon backgrounds for custom forms.
//
// @author Hugo Giraudel
// @param {String} $string - Initial string
// @param {String} $search - Substring to replace
// @param {String} $replace ('') - New value
// @return {String} - Updated string
@function str-replace($string, $search, $replace: "") {
$index: str-index($string, $search);
@if $index {
@return str-slice($string, 1, $index - 1) + $replace + str-replace(str-slice($string, $index + str-length($search)), $search, $replace);
}
@return $string;
}
// See https://codepen.io/kevinweber/pen/dXWoRw
@function escape-svg($string) {
@if str-index($string, "data:image/svg+xml") {
@each $char, $encoded in $escaped-characters {
$string: str-replace($string, $char, $encoded);
}
}
@return $string;
}
// Color contrast
@function color-yiq($color, $dark: $yiq-text-dark, $light: $yiq-text-light) {
$r: red($color);
$g: green($color);
$b: blue($color);
$yiq: (($r * 299) + ($g * 587) + ($b * 114)) / 1000;
@return if($yiq >= $yiq-contrasted-threshold, $dark, $light);
}
// Request a color level
@function color-level($color: $primary, $level: 0) {
$color-base: if($level > 0, $black, $white);
$level: abs($level);
@return mix($color-base, $color, $level * $theme-color-interval);
}