/** * Generic error typing for EcmaScript errors * Define `Error` here to avoid using `Error` from @types/node. * Using the `node` version causes a compilation error when this code is used as an npm library if @types/node is not already imported. */exportdeclareclassError{name?:string;message:string;stack?:string;constructor(message?:string);}/** * Used to exit the program and display a friendly message without the callstack. */exportdeclareclassFatalErrorextendsError{message:string;innerError:Error|undefined;staticNAME:string;constructor(message:string,innerError?:Error|undefined);}exportdeclarefunctionisError(possibleError:any):possibleErrorisError;exportdeclarefunctionshowWarningOnce(message:string):void;