Effect usage causes undesirable changes in behavior to existing components due to timing about angular HOT 4 OPEN

Using a transform callback on input may be helpful to address this issue to replace ngOnChanges/setter functionality, though that probably isn't the expected usage. The place this wouldn't work at the moment is the model() lacks a transform callback. Not sure if that is intentional, but it would be nice. For example, allow someone passing null or undefined to a model and convert the internal value to a default value.

This would mostly address the current functionality of setter and ngOnChanges using signals:

this.modelAttribute = model<string>('', { onChange: () => { ... });
this.inputAttribute = model<string>('', { onChange: () => { ... });

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In my prototyping, I have been trying to achieve signal based components and directives with no Angular lifecycle methods (ngOnChanges, ngOnInit, etc.).
I am not seeing a way without using ngOnInit

ngOnInit is not planned to go away in signal-based components. Does that resolve the issue for you?

From the RFC:

signal components have ngOnInit and ngOnDestroy only, and other hooks replaced by signal functionality.

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it would solve the initial invocation, but I guess the question is if computed() values would be re-computed if the values change but no one re-invokes computed to get a new values? Does it recompute when things change or only when the value is requested. I'm presuming it would be the latter? So that would work for the initial value, but it would lack the ngOnChanges equivalent functionality.

effect would work if it would be invoked before children components have their lifecycle handled

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Related question, would it be expected to use effect to implement structural directives or respond to inputs changing in any directive since directives have no templates to trigger the evaluation of something like a computed?

Running example: https://stackblitz.com/edit/stackblitz-starters-ndpvkk?file=src%2Fapp%2Fif-string.directive.ts

From the documentation, it seems like effect is really more for side-effects, but in a structural directive, there is no template that would cause the evaluation of a computed or other lifecycle methods that would trigger. This seems like a case where effect is required in order to go zoneless / with only signals. Is this the best practice? In the documentation, using them for directives or anything similar is not listed as a use case

The IfNumberDirective shows that computed will not work without the usage of ngOnChanges.

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