Skip object identifiers when checking for unused symbols

[dungpa]

UserVoice request: http://vfpt.uservoice.com/forums/247560-general/suggestions/8793808-do-not-mark-orange-in-the-right-bar-unused-self-re

Graying out object identifiers could be annoying. Since it has little practical value, we skip it while checking for unused references.

[vasily-kirichenko]

I'm afraid I disagree. What's more, that User Voice has only 4 votes. I like how it works now. Maybe we should ask people?

[dungpa]

Sure, please ask around on Twitter and Slack.

[vasily-kirichenko]

@cloudRoutine wrote on Slack:

I'd prefer another toggle like "Gray out unused member identifiers" and a toggle for whether unused items show up in the scroll bar

I agree, we should add two options:

• Syntax coloring
  • Gray out unused opens
  • Gray out unused declarations
    • Gray out unused self identifiers
  • Show unused symbols on scroll bar

BTW, what do you think about using "Highlight" instead of "Gray out"?

[cloudRoutine]

Highlight is more accurate since this is in the context of syntax highlighting and because the color for unused items doesn't have to be grey.

[dungpa]

Gray out unused self identifiers: the option is too fine-grained to support a very specific use case. I wouldn't want to go that way.

Show unused symbols on scroll bar: It might be useful, but it doesn't solve the problem here.

What do you think about using "Highlight" instead of "Gray out"?

Yes, it's better with 'Highlight' as @cloudRoutine said.

[vasily-kirichenko]

If you don't like the idea to add a setting for "Gray out unused self identifiers" and not all people like removing the feature (including me), I suggest to drop this PR.

[ashtonkj]

Please do make it optional. I consider the "this" identifier to be used as soon as a member is declared using the member this.membername syntax. I don't like being told that it isn't being used when it is required by the syntax (it feels like returning a false positive).

[vasily-kirichenko]

this is completely redundant. It's just a variable, and if you don't need it, you should claim about it explicitly, like _self or __. I think putting this everywhere is just old C# habit.

[dungpa]

This tweet convinced me https://twitter.com/CarstenK_Dev/status/631013723700903936.

Happy to close this PR and forget it forever.