empty deprecated in Record, but not in ReadonlyRecord

[fmpanelli]

Record and ReadonlyRecord are of course very similar.

I noticed that empty is deprecated in Record:

/**
 * Use a new `{}` instead.
 *
 * @since 2.0.0
 * @deprecated
 */
export const empty: Record<string, never> = {}

But it is not deprecated in ReadonlyRecord:

/**
 * @since 2.5.0
 */
export const empty: ReadonlyRecord<string, never> = {}

I am not sure if this is on purpose or I should raise an issue and propose a PR.

[gcanti]

@fmpanelli this is on purpose, empty in Record.ts is mutable, it shouldn't be used (hence the deprecation).

[DenisFrezzato]

Then I suggest to mention the reason why it's deprecated. What do you think?

[fmpanelli]

Giulio and Denis, I see your point and I would like to double-down on it.

And after experimenting a little bit I was able to write pretty indecent code also with readonlyRecord.empty.
Please, have a look at this crap of mine:

// Please! Don't do this at home!
function f(r: Record<string, unknown>) {
  r.a = 3;
}
const e = readonlyRecord.empty;
assert.deepStrictEqual(readonlyRecord.empty, {});
f(e);
assert.deepStrictEqual(readonlyRecord.empty, { a: 3 });

Maybe readonlyRecord.empty should also be considered harmful and deprecated?