Whoops, sorry, I made an assumption.
What I’ve done, which seems to work is something like:
let (signal, set) = create default_value in
let workaround = map (fun v -> set v) signal in
from_signal @@ map (fun v -> stuff I want to do) signal
Not ideal but the create in the version of React I’m using seems to guarantee there is a value there so it unblocks me until I find a more elegant solution.
Thank you for the quick response, @dbuenzli