Class 'SyntaxError' incorrectly implements interface 'Error'

[hildjj]

With the current peg.d.ts, I get this error when compiling typescript that uses peggy:

../../lib/peg.d.ts:345:9 - error TS2420: Class 'SyntaxError' incorrectly implements interface 'Error'.
  Type 'SyntaxError' is missing the following properties from type 'Error': name, message

345   class SyntaxError implements Error {
            ~~~~~~~~~~~


Found 1 error.

I think we might need to add:

    name: string;
    message: string;
    stack?: string;

to the class, or change it to an interface?

[Mingun]

Just need to change implements to extends -- this is one of special cases in TypeScript, where you should extend interface with class instead of implementing it.

[hildjj]

Yes, that works. I'll put a fix into the type testing patch I'm finishing up.