TypeAhead.kt

    private suspend fun handleTypeAhead(dataSource: Flow<String>, onChange: (results: List<String>) -> Unit) {

        // if a user is typing quickly wait for a pause before collecting most recent update. Ignore anything less then 3 characters.
        val resultsFromUser = dataSource.debounce(500).filter { it.length > 3 }

        // make an api call to get results for each user's query
        // transformLatest will cancel an older api call if a newer arrives first
        // this ensures a user will not see typeahead results for an out of date query
        val apiCalls = resultsFromUser.transformLatest {
            emit(getResultsAsync(it))
        }

        // pass the queries onto the subscriber. ex. the view to show these updates
        apiCalls.collect {
            onChange(it)
        }
    }