filter and regex issue

Question

I want to filter an array with a function.

if (this.pendingItems.customer?.emailAddresses) {
  this.pendingItems.customer.emailAddresses.filter(email => {
    isEmailValid(email);
  });
}

the function isEmailValid()

export function isEmailValid(s: string): boolean {
  const re =
    /^[a-z0-9+-][a-z0-9_+-]*(\.[a-z0-9_+-]+)*@([a-z0-9-]+\.)+[a-z0-9-]{2,}$/i;
  return re.test(s);
}

return the correct response (true or false) with the emails([email protected] and test2email) I pass it, but the filter don't work.

Answer 1

So the solution was:

if (this.pendingItems.customer?.emailAddresses) {
  this.pendingItems.customer.emailAddresses = this.pendingItems.customer.emailAddresses.filter(isEmailValid);
}

I forgot to reassign the variable ;p

Answer 2

You need to modify your expression slightly. The method you pass to the filter function should return true/false but it always returns void (which will be cast to false).

filter(email => isEmailValid(email))
or
filter(isEmailValid)
or
filter(email => { return isEmailValid(email) })

In case you missed it - you forgot to return the result of the isEmailValid ;)