selector_append($selectors...) Return a new selector with all selectors in $selectors appended one another as

unquote($string) Removes quotes from a string. If the string is already unquoted, this will return it unmodified.

desaturate($color, $amount) Makes a color less saturated. Takes a color and a number between 0% and 100%, and returns a color

set Return a new list, based on the list provided, but with the nth element changed to the value given.

grayscale($color) Converts a color to grayscale. This is identical to desaturate(color, 100%).

if($condition, $if-true, $if-false) Returns one of two values, depending on whether or not $condition is true

str_insert($string, $insert, $index) Inserts $insert into $string at $index.

scale_color($color, [$red], [$green], [$blue], [$saturation], [$lightness], [$alpha]) Fluidly scales one or more properties

variable_exists($name) Check whether a variable with the given name exists in the current scope or in the global scope.

to_upper_case($string) Converts a string to upper case.