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by anematode 5 days ago
Hm? JavaScript BigInts are arbitrary precision, and you need to use methods like BigInt.asIntN(64, a) to convert them to 64 bits
1 comments

I hate this so much because you can’t nicely serialise a BigInt as JSON. Using a string is nicer but it only makes sense where int64 is used as an ID, not where it’s used as a number; and you don’t wanna have to configure this per field per query.
You can serialize a BigInt by specifying a replacer:

    const obj = { a: 9007199254740993n }
    JSON.stringify(obj, (_key, value) => typeof value === 'bigint' ? JSON.rawJSON(value.toString()) : value)
And then you end up with strings on the other side, not numbers.
No you don't? The example I gave produces

    {"a":9007199254740993}
not

    {"a":"9007199254740993"}
Oh, that's much worse! The JSON string `{"a":9007199254740993}` decodes to the object `{"a":9007199254740992}` with typical JSON parsers like JavaScript's `JSON.parse`.
If you're applying a replacer, then you'd supply a reviver when parsing:

    const json = '{ "a": 9007199254740993 }'
    JSON.parse(json, (_key, value, context) => /^\d+$/.test(context.source) ? BigInt(context.source) : value)
IMO, I'm tending toward thinking that having types on your readable serialization format is a mistake, and that they should be always input to the (de)serializer instead.
JSON has arbitrary length numbers in the spec only.
Completely and utterly irrelevant.