Rationalise regular expressions in Kotlin lexer

[pyrmont]

Name of the lexer
Kotlin

Code sample

rouge/lib/rouge/lexers/kotlin.rb

Lines 27 to 30 in 7b87678

	name = %r'@?[_\p{Lu}\p{Ll}\p{Lt}\p{Lm}\p{Nl}][\p{Lu}\p{Ll}\p{Lt}\p{Lm}\p{Nl}\p{Nd}\p{Pc}\p{Cf}\p{Mn}\p{Mc}]*'
	name_backtick = %r'#{name}|`#{name}`'
	id = %r'(#{name_backtick})'

Additional context
Does id have any purpose? It's used throughout the lexer rather than name but as best as I can tell is just name inside a capture group. The capture group is never used, which seems wasteful.

Directing this at you, @lordcodes, because I'm not familiar with Kotlin and so am not sure if there would be a reason to have done things this particular way.

[lordcodes]

No, I had exactly the same thought when making changes to the Kotlin lexer. name_backtick can be used instead.

[pyrmont]

Perhaps this is going overboard but is it worth simply putting the backticks into the name regex as optional matches? It's a non-goal of Rouge to check syntax and so the fact this would allow: (1) backticks in places they shouldn't be; and (2) 'unbalanced' backticks, doesn't seem problematic to me. But what do you think? Perhaps overrationalising things?

[lordcodes]

Can be done, I am assuming name and name_backtick were kept separate to make the regexes easier to read.
I will have a look in more detail soon.

[pyrmont]

Yeah, if they were combined it's probably a good idea to include a code comment explaining that backticks are being included but will result in some technically false positives.