import { PhpAttributes, PhpNode } from './base';
import { PhpIdentifier } from './identifier';
import { PhpName } from './name';
/**
 * Represents a nullable PHP type (e.g., `?string`).
 *
 * @category PHP AST
 */
export interface PhpNullableType extends PhpNode {
    readonly nodeType: 'NullableType';
    readonly type: PhpType;
}
/**
 * Represents a PHP union type (e.g., `string|int`).
 *
 * @category PHP AST
 */
export interface PhpUnionType extends PhpNode {
    readonly nodeType: 'UnionType';
    readonly types: PhpType[];
}
/**
 * Represents a PHP intersection type (e.g., `A&B`).
 *
 * @category PHP AST
 */
export interface PhpIntersectionType extends PhpNode {
    readonly nodeType: 'IntersectionType';
    readonly types: PhpType[];
}
/**
 * Represents any valid PHP type node.
 *
 * @category PHP AST
 */
export type PhpType = PhpIdentifier | PhpName | PhpNullableType | PhpUnionType | PhpIntersectionType;
/**
 * Builds a nullable PHP type node.
 *
 * @category PHP AST
 * @param    type       - The type node to make nullable.
 * @param    attributes - Optional attributes for the node.
 * @returns A `PhpNullableType` node.
 */
export declare function buildNullableType(type: PhpType, attributes?: PhpAttributes): PhpNullableType;