It's a bit fiddly isn't it ?
What if my cursor, | is just before the in keyword (without a space) ?

let x : int option = |in

Or just after the = ?

Also I would expect Merlin's recovery to use a typed hole in such situation, but I guess it gets a ghost location preventing it to be used by construct ?

@voodoos
I have tried some case and I do not see any wrong behaviour since if it can't generate hole, it just fail with "Not an Hole", so it is the same behaviour if we had to put a hole.

I still find this a bit too hacky and specific, but there no real harm coming from it. Feel free to merge.

I still find this a bit too hacky and specific, but there no real harm coming from it. Feel free to merge.

What do you think about making it configurable?

Hi @shonfeder

After some experimentation and a bit of thought about the control, I think there are several undesirable behaviors (such as the fact that automatic hole insertion doesn't trigger a buffer change event), so I think it would be better to let the user implement his own additional logic at the personal configuration level rather than at the mode level (using, for example, the code you referenced in the issue). So I suggest closing this ticket, is that ok with you? (In any case, thank you very much for your suggestion and feedback!)