import { ValidationErrors } from '@angular/forms';
/**
 * Builds the message for a validator error from its payload, e.g.
 * `({ requiredLength }) => \`Pick at least ${requiredLength} items\``.
 */
export type FieldErrorMessageResolver = (error: any, key: string) => string;
/** Maps a validator error key to the message shown below a form field. */
export type FieldErrorMessages = Record<string, string | FieldErrorMessageResolver>;
/**
 * Shipped messages every field starts with, each one overridable. Covers the
 * validators Angular ships, so a field says what is actually wrong with it
 * without every application having to spell out the same sentences again.
 */
export declare const DEFAULT_FIELD_ERROR_MESSAGES: FieldErrorMessages;
/**
 * The message describing what a control is currently reporting: the consumer's
 * own message for that error, the shipped one, or `fallback` when the error has
 * no message mapped to it at all. Empty while the control is valid, which is
 * when a field shows its hint instead.
 */
export declare const resolveFieldErrorMessage: (errors: ValidationErrors | null | undefined, messages: FieldErrorMessages, defaults: FieldErrorMessages, fallback: string) => string;