import type { PropValue } from '../@types';
/**
 * The classes of the s-class_xxx directives (class:xxx on a kit tag):
 * - true gives the name (class:active -> active);
 * - a number or a text gives the name and the value, joined by a dash (class:gap={4} -> gap-4),
 *   without a dash when the name ends or the value starts with a separator (- _ : / .):
 *   s-class_gap-={4}, s-class_variant="-primary" and s-class_state=":active" keep working;
 * - false, null, undefined and '' give nothing.
 */
export declare function directiveClasses(classProps: Record<string, PropValue> | undefined): string[];
/**
 * Adds the classes of a value (one or several, separated by spaces) to the set.
 * The set keeps the first position of each class and drops the duplicates.
 */
export declare function addClasses(classes: Set<string>, value: string): void;
/**
 * Adds a class value with the rules of clsx (class on an element): a string, an array (nested too),
 * or an object whose keys are added when their value is truthy. Joining an array would give "a,b"
 */
export declare function addClassValue(classes: Set<string>, value: unknown): void;