import type { NestedValue } from './form';
export type Noop = () => void;
interface File extends Blob {
    readonly lastModified: number;
    readonly name: string;
}
interface FileList {
    readonly length: number;
    item(index: number): File | null;
    [index: number]: File;
}
export type Primitive = null | undefined | string | number | boolean | symbol | bigint;
export type BrowserNativeObject = Date | FileList | File;
/**
 * Registry of types which the recursive type helpers ({@link Path},
 * {@link DeepPartial}, FieldErrors, ...) treat as opaque leaf values
 * instead of recursing into their properties.
 *
 * Empty by default, so it has no effect until a consumer registers a type
 * via declaration merging. Useful for rich third-party value types (Dayjs,
 * Decimal, Luxon DateTime, ...) whose members should never be addressed by
 * a form path and can be expensive for the compiler to traverse.
 * @example
 * ```
 * declare module 'react-hook-form' {
 *   interface OpaqueTypes {
 *     dayjs: Dayjs;
 *   }
 * }
 * ```
 */
export interface OpaqueTypes {
}
/**
 * Union of all types registered in {@link OpaqueTypes}. `never` while the
 * registry is empty.
 */
export type OpaqueType = OpaqueTypes[keyof OpaqueTypes];
export type EmptyObject = {
    [K in string | number]: never;
};
export type NonUndefined<T> = T extends undefined ? never : T;
export type LiteralUnion<T extends U, U extends Primitive> = T | (U & {
    _?: never;
});
export type ExtractObjects<T> = T extends infer U ? U extends object ? U : never : never;
type IsPrimitiveLike<T> = T extends Primitive ? true : false;
export type DeepPartial<T> = IsPrimitiveLike<T> extends true ? T : T extends BrowserNativeObject | NestedValue | OpaqueType ? T : {
    [K in keyof T]?: ExtractObjects<T[K]> extends never ? T[K] : DeepPartial<T[K]>;
};
export type DeepPartialSkipArrayKey<T> = IsPrimitiveLike<T> extends true ? T : T extends BrowserNativeObject | NestedValue | OpaqueType ? T : T extends ReadonlyArray<any> ? {
    [K in keyof T]: DeepPartialSkipArrayKey<T[K]>;
} : {
    [K in keyof T]?: DeepPartialSkipArrayKey<T[K]>;
};
/**
 * Checks whether the type is any
 * See {@link https://stackoverflow.com/a/49928360/3406963}
 * @typeParam T - type which may be any
 * ```
 * IsAny<any> = true
 * IsAny<string> = false
 * ```
 */
export type IsAny<T> = 0 extends 1 & T ? true : false;
/**
 * Checks whether the type is never
 * @typeParam T - type which may be never
 * ```
 * IsNever<never> = true
 * IsNever<string> = false
 * ```
 */
export type IsNever<T> = [T] extends [never] ? true : false;
/**
 * Checks whether T1 can be exactly (mutually) assigned to T2
 * @typeParam T1 - type to check
 * @typeParam T2 - type to check against
 * ```
 * IsEqual<string, string> = true
 * IsEqual<'foo', 'foo'> = true
 * IsEqual<string, number> = false
 * IsEqual<string, number> = false
 * IsEqual<string, 'foo'> = false
 * IsEqual<'foo', string> = false
 * IsEqual<'foo' | 'bar', 'foo'> = boolean // 'foo' is assignable, but 'bar' is not (true | false) -> boolean
 * ```
 */
export type IsEqual<T1, T2> = T1 extends T2 ? (<G>() => G extends T1 ? 1 : 2) extends <G>() => G extends T2 ? 1 : 2 ? true : false : false;
export type DeepMap<T, TValue> = IsAny<T> extends true ? any : T extends BrowserNativeObject | NestedValue | OpaqueType ? TValue : T extends ReadonlyArray<infer U> ? Array<DeepMap<NonUndefined<U>, TValue> | undefined> : T extends object ? {
    [K in keyof T]: DeepMap<NonUndefined<T[K]>, TValue>;
} : TValue;
export type IsFlatObject<T extends object> = Extract<Exclude<T[keyof T], NestedValue | Date | FileList | OpaqueType>, any[] | object> extends never ? true : false;
export type Merge<A, B> = {
    [K in keyof A | keyof B]?: K extends keyof A & keyof B ? [A[K], B[K]] extends [object, object] ? Merge<A[K], B[K]> : B[K] : K extends keyof A ? A[K] : K extends keyof B ? B[K] : never;
};
export {};
//# sourceMappingURL=utils.d.ts.map