Which @angular/* package(s) are relevant/related to the feature request?

No response

Description

In a signal world, we tend use signal to trigger the framework's reactivity.

Pipes, which date back to Angular.js times, are used to memoise function call (a bit like a computed) but don't fit well with signals today.

Among others here are the key caracteristics of Pipes

• Can be reused accross components
• Pipes instance are instantiated during the creation phase of the template
• Pipes can inject instances from DI
• Pure pipes are memoized, meaning that they only re-run when at least one of their parameters changes
• They can can be used without any additional defintion in the component implementation

On the other hand signals, mainly computed :

• Need to be define in the component
• Cannot be defined in a template, for example using items of a @for block.
  • We don't have syntax to define one in templates, to be defined only in creation mode
• The usage of DI rely on the injection at the component level

We can also note (cf #56401) that signals in the transform implementation of pure pipes don't trigger any reactivity.

This is to sum-up that the intersection of Pipes and signal is today incomplete an does address the developer's expectations.