createFieldSync

Description#

Bidirectional Field <-> control value sync via CngxFormFieldPresenter.

Two effect()s, each reading the opposite branch inside untracked() with valueEquals as the cycle break - the canonical bridge every model()-based cngx control reuses instead of re-implementing field write-back. Both the field and the control's model() are writable sources of truth, so this is coordination, not a single computed(). Requires an injection context; no-op without a surrounding cngx-form-field.

Keeps the create* prefix despite calling inject() in its body: it is a blessed exception (see architecture-summary, mirrors adaptFormControl), not an oversight. The name is also the public @cngx/forms/select export; renaming would break that contract.

createFieldSync<number>({
  componentValue: this.value,
  valueEquals: Object.is,
  coerceFromField: (v) => (typeof v === 'number' ? v : 0),
});