I have a `List<Person>` but I want to filter...

# getting-started

[Colton Idle]

I have a List<Person> but I want to filter out if Person.socialSecurityNumber is null. Easy.

But what If I want to log each time that filter is hit. Essentially we're trying to be proactive about catching cases where socialSecurityNumber is null because it should "never" be.

[Colton Idle]

Basically have this right now

people
    .filter(predicate = { it.social != null }

but in an ideal world, I kinda want is this?

people
    .filter(predicate = { it.social != null }, predicateFailedSideEffect = { Sentry.log(it.id) })

[Shawn]

you could partitionBy and maybe use the scope functions to jerry-rig a call chain that includes logging?

[Shawn]

val peopleWithSsns = people.partition { it.ssn != null }
  .apply { second.forEach { Sentry.log(it.id) } }
  .first

[José González D'Amico]

it should "never" be ? what about illegal inmigrants?

[Arjan van Wieringen]

Not knowing the domain and country of OP we have no clue whether or not never really is never. Obligatory US SSN movie btw

https://www.youtube.com/watch?v=Erp8IAUouus▾

[Javier]

people
    .onEach { if (it.social == null) log(...) }
    .filter { it.social != null }