Fsharp: F# tooltip errors interfering with tooltip documentation; show both?

[JasonKleban]

Yes, I'm doing something wrong - that's why I need to see the documentation for this function so I can fix it or rule it out as the problem.

I get stuck by this UI glitch all the time.

[dsyme]

This can definitely be a problem.

We could do with more details here per CONTRIBUTING.md - an exact repro including code and instructions. We need to be able to know that we've fixed the problem you're actually seeing. Thanks

[JasonKleban]

Yes sir. I don't think I fully understand the circumstances of when this occurs but I'll give it a shot here - probably not very good.

Repro

/// (Documentation) Use this one for numbers
let generateFunN ( m : int ) = fun i -> m + i

/// (Documentation) Use this one for strings
let generateFunS ( m : string ) = fun s -> m + s

(* This just reverses the params of map to contrive an example 
where the function is based on the 'a of the 'a list instead
of the other way around *)
let mapOver sequence selector = Seq.map selector sequence

let bugged = mapOver [ "a"; "b"; "c" ] (generateFunN 4)       
let  works = mapOver [ "a"; "b"; "c" ] (generateFunS "def")

I think the fparsec case I started with has more to do with generics but I reduce that case to this sample. I tried to make generateFun be generic over anything with (member (+)) but I think I was running into value restriction issues(?)

Actual

In the animation there I'd presumably need to read the signature/documentation that generateFunN should be used for numbers and not for strings but I cannot see that because the presumably unhelpful-in-this-case type error is taking precedence.

Expected

I'd like to be able to see both, perhaps with the up-down arrows like overloaded signatures typically offer - the error description would just be inserted as the first pane or whatever.

Severity

This seems to come up a lot for me and interrupt my productivity, but funny, when I tried to manufacture the situation I had a hard time making it happen (even though it is complete consistent).

Version

F# 4.0 in Visual Studio 2015

Likely cause

I think it has to do with the generic(?) function return value being the issue rather than a parameter within the function.

Workaround

You can delete enough characters of the function name so that there are multiple options to chose among, then you can scroll through and see the documentation. Or you can go-to-definition.

[dsyme]

For workarounds - you can also usually press Ctrl-Space on the identifier to get the autocomplete information.

[dsyme]

BTW this is how it's always been, I guess I've just got used to it. But it is sub-optimal.

[cloudRoutine]

We list the errors above the intellisense in Ionide

it's quite useful in less trivial cases :smiley:

[smoothdeveloper]

This is annoying behaviour in VS when having warning as errors and getting the symbol is not used message.

Type information and member documentation should always appear in tooltip if the type checking is done succesfully, it would be great to have this behaviour change in future version of Visual F#.

[saul]

Not sure exactly what PR this was fixed in, but here's what current master looks like:

This can be closed now.