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b96f65a963
Previously, navigating a `FieldTree` in signal forms involved reactive reads
of the value of the parent field(s), both directly and via `.childrenMap()`.
This meant that on _any_ change to the value of a field, reactive
notifications would trigger updates of computeds, reruns of effects, etc.
So for example, this effect would run on every change to the form:
```ts
const f = form(signal({data: 'abc', unrelated: 0}));
effect(() => {
// accessing f.data incurs a dependency on f().value() which changes
// on every change in the whole form
console.log(f.data().value());
});
```
This is deeply counterintuitive and troublesome when attempting to write
effect logic, and also results in `computed`s unnecessarily updating.
This change introduces the concept of a "reader" computed, which memoizes
the access of a field at a given key via the reactive graph. With this, the
same `f.data` access above now depends on the `data` reader in `f` only,
which is effectively a constant computed. As a result, the effect only
reruns on changes to `data`'s value, as intended.
PR Close #65802
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| .. | ||
| animations | ||
| benchpress | ||
| common | ||
| compiler | ||
| compiler-cli | ||
| core | ||
| docs/di | ||
| elements | ||
| examples | ||
| forms | ||
| language-service | ||
| localize | ||
| misc/angular-in-memory-web-api | ||
| platform-browser | ||
| platform-browser-dynamic | ||
| platform-server | ||
| private/testing | ||
| router | ||
| service-worker | ||
| ssr/docs | ||
| upgrade | ||
| zone.js | ||
| BUILD.bazel | ||
| circular-deps-test.conf.js | ||
| empty.ts | ||
| goog.d.ts | ||
| license-banner.txt | ||
| package.json | ||
| README.md | ||
| system.d.ts | ||
| tsconfig-build.json | ||
| tsconfig-legacy-saucelabs.json | ||
| tsconfig-test.json | ||
| tsconfig.json | ||
| tsec-exemption.json | ||
| types.d.ts | ||
Angular
The sources for this package are in the main Angular repo. Please file issues and pull requests against that repo.
Usage information and reference details can be found in Angular documentation.
License: MIT