Where did PipeTransform is not defined / Angular 2 get lost?

Question

JavaScript

I'm trying to write a search filter in an Angular2 application.
ts code:

import { Component } from '@angular/core';
import { Pipe,PipeTransform } from '@angular/core';

@Pipe({
    name: 'searchFilter'
})

export class SearchFilter implements PipeTransform {
    transform(items: any[], criteria: any): any {

        return items.filter(item => {
           for (let key in item ) {
             if((""+item[key]).includes(criteria)){
                return true;
             }
           }
           return false;
        });
    }
}

@Component({
  selector: 'releases-component',
  templateUrl: './app/releases/releases.component.html',
  styleUrls: ['./app/releases/releases.component.css']
})
export class ReleasesComponent  { 
  this.releases;
}

html code:

<div class="menu">
  <div class="search">
    <input type="text" placeholder="Search for places of interest here">
  </div>
</div>

<div class="resultsOutlet">
  <ul>
       <li *ngFor="let place of (places | searchFilter: search.value )">(...)</li>
    </ul>
</div>

I get an error PipeTransform is not defined . I can't figure out why.
Imported into the PipeTransform component, into the module too:

@NgModule({
  imports:      [ BrowserModule, HttpModule, routing],
  declarations: [ AppComponent, 
  				  HomeComponent, 
  				  PlacesComponent, 
  				  Pipe,
  				  PipeTransform],
  bootstrap:    [ AppComponent ]
})

True, Pipe is highlighted in a different color (in Sublime Text 3) for some reason, but the compiler has no complaints about it, it seems.