fix: avoid const enum and deprecate DeepResolveType

[dai-shi]

ref: #327 (comment)
close #292

AsRef const enum was introduced in #146 to fix some typing issue with snapshot. But, this causes some trouble while explicitly typing it, without any workarounds.

This changes AsRef to be hopefully unique type. This allows types to be inferred. While we don't recommend, you can define the same AsRef on your end. It was our strong hope to hide the internal type as implementation detail and it's finally possible.

DeepResolveType was exported previously (which is not considered a public api, but someone might have used it), but it's now deprecated.

Migration Guide

In case you need to specify snapshot types, there are two options.

Assert mutable (let's lie)

type State = { foo?: string }
const state = proxy<State>({})

  const snap = useSnapshot(state) as State
  const handleSnap = (s: State) => {
    // ...
  }

Wrap types with Readonly<>

type State = { foo?: string }
const state = proxy<State>({})

  const snap = useSnapshot(state)
  const handleSnap = (s: Readonly<State>) => {
    // ...
  }

If the state is deeply nested, please define DeepReadonly type util.

type DeepReadonly<T> = {
  readonly [P in keyof T]: DeepReadonly<T[P]>;
}

  const handleSnap = (s: DeepReadonly<State>) => {
    // ...
  }

Other hacks

Extract the return type of snapshot

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[github-actions]

Size Change: -157 B (0%)

Total Size: 31.7 kB

Filename	Size	Change
dist/macro.js	910 B	-6 B (-1%)
dist/system/macro.js	721 B	-12 B (-2%)
dist/system/utils.js	3.44 kB	-63 B (-2%)
dist/system/vanilla.js	1.98 kB	-43 B (-2%)
dist/umd/macro.js	1.06 kB	-11 B (-1%)
dist/umd/utils.js	4 kB	-18 B (0%)
dist/umd/vanilla.js	2.1 kB	-18 B (-1%)
dist/utils.js	3.84 kB	+14 B (0%)

ℹ️ View Unchanged

Filename	Size
dist/esm/index.js	1.36 kB
dist/esm/macro.js	613 B
dist/esm/utils.js	3.22 kB
dist/esm/vanilla.js	1.84 kB
dist/index.js	1.45 kB
dist/system/index.js	1.59 kB
dist/umd/index.js	1.59 kB
dist/vanilla.js	1.96 kB

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