Metals: SymbolKind for val should not be constant

[olafurpg]

User is val (icon is kinda ugly in vscode with https://marketplace.visualstudio.com/items?itemName=patrys.vscode-code-outline)

User is var

I feel that constant is not appropriate for vals since vals can be very stateful objects, constants are IMO literals like "string" and 2

[laughedelic]

For literals there are SymbolKinds like String, Number, Boolean, Array.

I think that SymbolKinds don't map well on the entities in Scala, but we should try to use more of them just for visual distinction. Here's how val vs. var looks in Atom:

I think it kind of makes sense and would be wrong to mark both val and var with the same kind/icon. Icons design is, of course, something editor-specific and could be improved, but the set of symbol kinds is a part of LSP and is harder to change, I think.

[laughedelic]

Also, here is the full list of symbols/icons in the two editors:

[ShaneDelmore]

I would have thought Constant meant single assignment, but it sounds like @olafurpg has the intuition that Constant means literal. They seem to already have icons for String, Number, and Boolean which would cover a good deal of @olafurpg interpretation of Constant (wouldn’t it?) but I don’t see anything else available that covers a single assignment value. Of these admittedly not wonderful options I prefer Constant still, but is it worth proposing another symbol kind to LSP? As for icons, that feels unrelated, we can always contribute better icons.

[ShaneDelmore]

For what it’s worth, I like the atom icons, visually one looks like it changes over time, and the other looks like it is assigned once to my eye.

[olafurpg]

I guess I'm just unhappy with the icon for outline types in the vscode plugin for "Constant", in atom it looks more sensible. I agree we should have a different symbol kind of vars and vals.

[laughedelic]

Check https://github.com/patrys/vscode-code-outline/issues/4 and https://github.com/Microsoft/vscode/issues/28592: the imcons have to be iproved in the VSCode itself. I tried to search a bit related issues in the vscode repo and I got an impression that it's not considered an big problem.. 🙁
Also related: https://github.com/Microsoft/vscode/issues/2628 (didn't read completely, but it's about having more kinds) and https://github.com/Microsoft/vscode/issues/23927 (about modifiers for symbol kinds)

[olafurpg]

I can live with it 😸