In this example, a GitHub username searchbox is rendered to the screen. The searchbox includes a typeahead, which fetches username suggestions based on what the user has typed so far.
When a user clicks on a suggestion, or presses the return key while the textbox (or a suggestion) is focused, the selected GitHub account's data is fetched, and rendered to the screen.
Two sources are observed in this example:
search prop is used as the source for two separate streams.
First, a stream of suggestions. Each time the
search prop changes, if its value is truthy, it is debounced and sent through a pipeline which includes an asynchronous fetch request, and some data manipulation.
In a separate stream of logic, each time the
search prop changes, if its value is an empty string, it is mapped to another
setState effect which resets the
suggestions state to an empty array.
Finally, a stream of users. Each time the
selection prop changes, it is sent through a similar logic pipeline to the first stream, which results in the
user state being updated.
These three streams are merged into one, and returned as the output of the
Note that all three streams used a
toState "effectCreator" function at the end - this is a helper function similar to a redux
If the effect's type is
handler passes the effect's payload into
The end result is an intelligent user interface which exposes search suggestions and fetches user data as a side-effect.