import { PDFObject } from './pdf-object.ts';
import type { PDFWriter } from './pdf-writer.ts';
/**
 * Represents a PDF dictionary object, which is a collection of
 * key-value pairs.
 */
export declare class PDFDict extends PDFObject {
    private readonly entries;
    /**
     * Creates a PDFDict from a given object mapping strings to PDFObjects
     * or primitive values. Undefined values are skipped.
     */
    static of(object: Record<string, PDFObject | string | number | boolean | null | undefined>): PDFDict;
    /**
     * Creates an empty PDFDict.
     */
    constructor();
    [Symbol.iterator](): Iterator<[string, PDFObject]>;
    /**
     * Returns an array of the dictionary's keys.
     */
    keys(): string[];
    /**
     * Sets a key-value pair in the dictionary.
     */
    set(name: string, value: PDFObject | string | number | boolean | null): void;
    /**
     * Gets the value for a given key in the dictionary, or `undefined` if
     * the key does not exist.
     */
    get(name: string): PDFObject | undefined;
    /**
     * Updates the value for a given key using the provided updater function.
     * If the updater returns a different value, the dictionary is updated.
     * Returns the updated value.
     */
    update(name: string, updater: (prev: PDFObject | undefined) => PDFObject): PDFObject;
    /**
     * Returns the number of entries in the dictionary.
     */
    size(): number;
    /**
     * Writes the PDF dictionary to the given PDFWriter.
     */
    write(writer: PDFWriter): void;
}