Narrow Json error types

[thewilkybarkid]

JSON.parse and JSON.stringify only throw SyntaxError and TypeError respectively, so we can narrow the types in the Json module.

There is one custom error in stringify, but this is better represented as a TypeError anyway.

[enricopolanski]

I like the proposal, I think though that we are missing a case?

JSON.stringify({x: 2n});
// TypeError: BigInt value can't be serialized in JSON

Should we handle both the TypeErrors messages rather than only cyclic references?

[thewilkybarkid]

Having tried this out for a bit, these types are a bit problematic: TypeError and SyntaxError are just aliases of Error.

So, I'd probably say to create new error types, or just use Error (which is better than the original unknown).