Combine long_flag and long_flag_aliases into one API?

[SUPERCILEX]

Clap currently has https://docs.rs/clap/latest/clap/struct.Command.html#method.long_flag and https://docs.rs/clap/latest/clap/struct.Command.html#method.long_flag_aliases where long_flag_aliases does nothing without long_flag being specified. One could add a runtime warning/crash, but it's usually better to make bad states unrepresentable. The proposed solution is to unify these APIs into a long_flags method.

Actually, the reason the "alias" method variants exist is to allow having hidden long flags that don't show up in help. I think the next best solution to use a builder pattern to only allow calling the alias variants after having specified the base long flag.

[epage]

Not finding an issue for this but I believe there has been a request to have a subcommand flag without a name. This would mean we need a canonical long_flag.

I think the next best solution to use a builder pattern to only allow calling the alias variants after having specified the base long flag.

Without what I stated above, hidden doesn't really make a difference. The desire to force a visible flag when dealing with invisible aliases applies just as much to Args.

I think the next best solution to use a builder pattern to only allow calling the alias variants after having specified the base long flag.

Relying on the type state pattern in a build API can severely complicate it especially for a runtime-focused API like clap's.