Convert SintaxKind marker name to the real kind name

getSyntaxKindName.ts

    export function getSyntaxKindName(kind: SyntaxKind): string
    {
        const markers: { [name: string]: string } = {
            FirstAssignment         : "EqualsToken",
            LastAssignment          : "CaretEqualsToken",
            FirstCompoundAssignment : "PlusEqualsToken",
            LastCompoundAssignment  : "CaretEqualsToken",
            FirstReservedWord       : "BreakKeyword",
            LastReservedWord        : "WithKeyword",
            FirstKeyword            : "BreakKeyword",
            LastKeyword             : "OfKeyword",
            FirstFutureReservedWord : "ImplementsKeyword",
            LastFutureReservedWord  : "YieldKeyword",
            FirstTypeNode           : "TypePredicate",
            LastTypeNode            : "LiteralType",
            FirstPunctuation        : "OpenBraceToken",
            LastPunctuation         : "CaretEqualsToken",
            FirstToken              : "Unknown",
            LastToken               : "LastKeyword",
            FirstTriviaToken        : "SingleLineCommentTrivia",
            LastTriviaToken         : "ConflictMarkerTrivia",
            FirstLiteralToken       : "NumericLiteral",
            LastLiteralToken        : "NoSubstitutionTemplateLiteral",
            FirstTemplateToken      : "NoSubstitutionTemplateLiteral",
            LastTemplateToken       : "TemplateTail",
            FirstBinaryOperator     : "LessThanToken",
            LastBinaryOperator      : "CaretEqualsToken",
            FirstNode               : "QualifiedName",
            FirstJSDocNode          : "JSDocTypeExpression",
            LastJSDocNode           : "JSDocPropertyTag",
            FirstJSDocTagNode       : "JSDocTag",
            LastJSDocTagNode        : "JSDocPropertyTag",
            FirstContextualKeyword  : "AbstractKeyword",
            LastContextualKeyword   : "OfKeyword",
        }

        const name = SyntaxKind[kind];
        return markers.hasOwnProperty(name) ? markers[name] : name;
    }

This will not break in future versions. ( above is no longer valid )

function createEnumWithMarkerToString<T extends number = number>(enumeration: any){
  const map:Map<number, string> = new Map();
  for(let name in enumeration){
      const id = enumeration[name];
      if(typeof id === 'number' && !map.has(id)){
          map.set(id, name);
      }
  }
  return (value:T) => map.get(value) as string; //could be undefined if used the wrong enum member..
}

const syntaxKindToString = createEnumWithMarkerToString<SyntaxKind>(SyntaxKind);

const withKeywordIsAMarker = SyntaxKind.WithKeyword;

console.log(SyntaxKind[withKeywordIsAMarker]); // LastReservedWord
console.log(syntaxKindToString(withKeywordIsAMarker)); // WithKeyword
console.log(syntaxKindToString(SyntaxKind.LastReservedWord)) // WithKeyword