Validation Exceptions

import { validate, Exception } from "bycontract";
try {
  validate( 1, "NaN" );
} catch( err ) {
  console.log( err instanceof Error ); // true
  console.log( err instanceof TypeError ); // true
  console.log( err instanceof Exception ); // true
  console.log( err.name ); // ByContractError
  console.log( err.message ); // expected nan but got number
}