invert($color) Returns the inverse (negative) of a color. The red, green, and blue values are inverted, while the opacity

hue($color) Returns the hue component of a color. See

unitless($number) Returns whether a number has units.

max($numbers...) Finds the maximum of several numbers. This function takes any number of arguments.

map_has_key($map, $key) Returns whether a map has a value associated with a given key.

type_of($value) Returns the type of a value.

mixin_exists($name) Check whether a mixin with the given name exists.

map_merge($map1, $map2) Merges two maps together into a new map. Keys in $map2 will take precedence over keys

is_superselector($super, $sub) Returns whether $super is a superselector of $sub. This means that

counter($args...) This function only exists as a workaround for IE7‘s