let's say I have a `suspend fun sum(): Long` insid...

# coroutines

[jw]

let's say I have a suspend fun sum(): Long inside which I have a reference to something with the method suspend fun consume(consumer: suspend (Long) -> Unit). The implementation is the obvious thing:

var sum = 0L
numbers.consume { sum += it }
return sum

Now let's say I want to specify a maximum number of numbers. How can I cause the numbers.consume to stop pushing numbers at me once that max is hit?

[elizarov]

The obvious thing is by throwing an exception, but that should be only used for exceptional circumstances. If you want to support that kind of limit for normal operations, then you should plan for that in your consumer signature, e.g. define it as consumer: suspend (Long) -> Boolean where the resulting boolean indicates whether consumer is ready to accept more.