Angular2 RC6 pipes. Can I declare a pipe within the same .ts file as my component?

Question

Do I have to register every single pipe within @ngModule? I have one which is used by single specific component only. Would be nice to declare it right in the same file, so nothing else is aware about it. I believe that was possible before - just can't find the right syntax.

Thank you.

Answer 1

Every Pipe, Component and Directive must be declared in a Module. This is because the compiler relies on the module's declarations to parse templates. If it hasn't seen MyPipe in the module's declarations (or the declarations of an imported module), then it will not look for it nor recognize it when you use the pipe in the template

If it's important that no other component be able to see your Pipe, create a module that contains only the component that uses the pipe and the pipe itself, and do not export the pipe.

import { NgModule }      from '@angular/core';
import { CommonModule }  from '@angular/common';
import { MyPipe }        from './my.pipe';
import { MyComponent }   from './my.component';

@NgModule({
  imports:      [ CommonModule ],
  declarations: [ MyComponent, MyPipe ],
  exports:      [], // don't export what you want to keep private
  providers:    []
})
export class MyModule { }

Answer 2

Since RC6, the pipes property has been removed from ComponentTypeMetadata , you have to register them in NgModule.