JavaScript

1883 readers

1 users here now

founded 1 year ago

MODERATORS

erlingur@programming.dev

Ategon@programming.dev

nick@programming.dev

New JavaScript Set methods (developer.mozilla.org)

submitted 2 months ago by neme@lemm.ee to c/javascript@programming.dev

3 comments fedilink hide all child comments

you are viewing a single comment's thread
view the rest of the comments

[–] Kissaki@programming.dev 3 points 2 months ago* (last edited 2 months ago) (1 children)

Where would/should the mapping happen? Probably not the Set constructor. JSON.parseSet()?

JSON.parseSet = json => new Set(JSON.parse(json));
JSON.parseSet('["A", "B", "C", "A", "B"]'); // Set(3) [ "A", "B", "C" ]

/edit: JSON.parseMap()

JSON.parseMap = json => new Map(Object.entries(JSON.parse(json)));
JSON.parseMap('{"a":1,"b": 2}'); // Map { a → 1, b → 2 }

[–] kinttach@lemm.ee 2 points 2 months ago

There also needs to be some way to indicate that a JSON construct is a Set, Map, plain object, or array. You’d want a date/time type as well.

Without breaking existing JSON parsers, the way to do that is to add metadata like a _type field to an object, or to add a “sidecar” object like superjson does. Which works but is ugly IMO.

Then there’s BSON, YAML, JSON Schema, and the one we don’t mention ₓₘₗ. To my knowledge all of those could be extended in a way to support new types, but require the producer and consumer to both understand and follow whatever convention you use. They lack the universal interchangeability of JSON.