import type { Args, Fn } from "../HKT";
import type { AssertStr, Eq } from "../helpers";

/**
 * Convert a bigint to a string.
 *
 * Sig: `(n: bigint) => string`
 */
export type ToStr<N extends bigint> = AssertStr<
  Eq<N, bigint> extends true ? "bigint"
  : N extends bigint ? `${N}n`
  : string
>;

/**
 * [Fn] Convert a bigint to a string.
 *
 * Sig: `(n: bigint) => string`
 */
export default interface ToStrFn extends Fn<[bigint], string> {
  def: ([n]: Args<this>) => ToStr<typeof n>;
}