Implement StringLiteral#count

[Blacksmoke16]

Implements StringLiteral#count.

[bcardiff]

I’m courious, was this feature needed in some use case?

[Blacksmoke16]

I needed it to count the number of placeholder values in a URL path, i.e. "/users/:user_id/posts/:post_id".count(':').

Other way to do it would be like "path".chars.select { |chr| chr == ':' }.size. This way is quite a bit cleaner.

[j8r]

@Blacksmoke16 you can do "/users/:user_id/posts/:post_id".split(':').size}}

[straight-shoota]

At some point we need to establish some consistent policy how to decide which methods should be available in the macro language. We shouldn't port all of String to StringLiteral.

But I don't see a reason why not to merge this and it has a use case. There are workarounds, but they obscure meaning.

[asterite]

Yes, right now there's no clear policy about which macro methods should exit. However, we should probably have all methods from string and all non-mutating methods from array/hash to allow simpler macro code to be written.