pipes.md

• What is a pure pipe?

• What is an async pipe?

• What kind of data can be used with async pipe?

• How do you create a custom pipe?

• How does async pipe prevents memory leeks?

Async pipe knows about the lifespan of the component and unscubscribes from the observable if necessary.

• What is the difference between pure and impure pipes?

  Pure Pipes:

  • Input parameters value determine the output so if input parameters don’t change the output doesn’t change.
  • Can be shared across many usages without affecting the output result.
  • Pure pipes are pure functions that are easy to test.

  Impure Pipes:

  • Cannot use the input value to determine if the output will change.
  • Cannot be shared because the internal state can be affected from outside.