How to print size of flow in kotlin

Solution 1:

A Flow doesn't know its size at any moment, because there is an unknown number of future values to be emitted. Also, Flows do not keep a record of how many values they have emitted in the past.

Sequences have the same problem. With both Flows and Sequences, you can only get the count by doing something terminal with them, something that iterates through it all.

The only way to get the size of the Flow is to do something that iterates through the entire Flow. For instance, you can call the suspend function count() on a Flow to get its size. The more complicated way to do it would be to create a count variable and then increment the count inside a collect call. However, counting the emissions of a Flow is only usable for finite cold Flows. Hot flows (SharedFlow and StateFlow) are never finite, and many cold Flows are also infinite.