example suggestion: pattern matching on `Task`

It may be tempting to try pattern matching (similar to result) like this:

when Stdin.line is
    Ok (Input str) -> str
    _ -> "" 

But what you actually want here is:

Task.map
    Stdin.line
    \readInput ->
        when readInput is
            Input str -> str
            End -> ""

This definitely feels worth an example.
I recommend doing one with Stdin.line and something like Env.cwd (with Task.attempt).

Start by locating the existing Roc examples and the conventions for demonstrating Task, Stdin.line, Env.cwd, and Task.attempt. Add an example showing Task.map over Stdin.line with the Input and End cases, alongside an Env.cwd example using Task.attempt; done means both suggested patterns are clearly demonstrated.