Angular2 Filter issue

Here's how I am using the filter:

  <ion-item *ngFor="let contact of contacts | isMember">
           <ion-label>{{contact.name}}</ion-label>

           {{contact.phoneNumber}}-{{contact.isMember}}
       </ion-item>

Filter definition below:

import { Pipe, PipeTransform } from '@angular/core';
@Pipe({name: 'isMember'})
export class IsMemberPipe implements PipeTransform {
    transform(value: any): any {

        if (value.isMember === true) {
            return value;
        }
        return undefined;

    }
}

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Question

Goal is to only display rows that have isMember flag set to true.
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Answers

Just ensure your pipe doesn't explode when null is passed in as value

if (value && value.isMember === true) {