///
/// Gets the index of the passed key
///
/// @access private
///
/// @param {String} $key - breakpoint key
///
/// @return {Number}
///
/// @group Internal Functions
///
@function flint-get-index($key) {

    @for $i from 1 through length(map-keys(flint-get-value("breakpoints"))) {
        @if flint-steal-key($i) == $key {
            @return $i;
        }
	}

    @return false;
}