import { type Injector } from '@angular/core';
/**
 * Options for the `injectAttribute` function.
 */
export type InjectAttributeOptions<T = unknown> = {
    /**
     * Custom injector to use for dependency injection.
     */
    injector?: Injector;
    /**
     * Transform function to convert the string attribute value to the desired type.
     * This is useful for type coercion (e.g., string to number or boolean).
     */
    transform?: (value: string) => T;
};
/**
 * Injects the value of a host attribute with a default value if the attribute is not present.
 * This is a simplified wrapper around Angular's `HostAttributeToken`
 *
 * @template T - The type of the attribute value
 * @param {string} key - The name of the attribute to inject
 * @param {T} defaultValue - The default value to return if the attribute is not present
 * @param {InjectAttributeOptions} options - Optional configuration for the injector
 * @returns {T} The attribute value or the default value
 *
 * @example
 * ```ts
 * export class Button {
 *   variation = injectAttribute<'primary' | 'secondary'>('variation', 'primary');
 * }
 * ```
 *
 * @example
 * <app-button variation="secondary" />
 */
export declare function injectAttribute<T>(key: string, defaultValue: T, options?: InjectAttributeOptions<T>): T;
/**
 * Injects the value of a host attribute that must be present.
 * Throws an error if the attribute is not provided.
 *
 * @template T - The type of the attribute value
 * @param {string} key - The name of the attribute to inject
 * @param {InjectAttributeOptions} options - Optional configuration for the injector
 * @returns {T} The attribute value
 * @throws {Error} If the attribute is not present in the host element
 */
export declare namespace injectAttribute {
    function required<T>(key: string, options?: InjectAttributeOptions<T>): T;
}