interface Deno.DiagnosticPropertiesoptionalmessageText: stringA string message summarizing the diagnostic. optionalmessageChain: DiagnosticMessageChainAn ordered array of further diagnostics. optionalrelatedInformation: Diagnostic[]Information related to the diagnostic. This is present when there is a suggestion or other additional diagnostic information optionalsourceLine: stringThe text of the source line related to the diagnostic. optionalsource: stringoptionalstart: { line: number; character: number; }The start position of the error. Zero based index. optionalend: { line: number; character: number; }The end position of the error. Zero based index. optionalfileName: stringThe filename of the resource related to the diagnostic message. category: DiagnosticCategoryThe category of the diagnostic. code: numberA number identifier.