derive arguments like this:
#[arg(long)]
pub flag: bool,
were producing option descriptions like this:
--flag=FLAG
FLAG is spurious. It turns out that derive always sets a value name, for
simplicity, even when there are no arguments. Check for this case.
Fixes#4443.
This is an intermediate solution for #4408. As there were no agreeed
upon goals, I went with what I felt read well and that I saw commonly
used on non-clap commands.
- "information" isn't really a necessary word.
- I originally favored `Print this help` but realied that doesn't read
correctly in completions.
- Besides being shorter, the reason for the flipped short/long hint is
it gives people the context they need for scanning, emphasizing
"summary" and "more".
Fixes#4409
This was ported over from the usage parser which modeled after docopt.
We just never got around to implementing the rest of the syntax.
However, when considering this as a standalone feature, an
`arg!(--flag <value>)`, outside of other context, should be optional.
This is how the help would display it.
Fixes#4206
In reviewing CLIs for #4132, I found some were providing helps on `-h`
vs `--help` and figured that could be built directly into clap. I had
considered not making this hint automatic but I figured the overhead of
checking if long exists wouldn't be too bad. The code exists (no binary
size increase) and just a simple iteration is probably not too slow
compared to everything else.
Fixes#1015
This adds feature parity for mangen with the standard help output. Users
will now see the list of possible values for value arguments.
One change that was made to make this possible was adding the method
`get_possible_values` to the public API for an arg. I tried to think of
a way to get around this, but because this is the interface that the
help generation uses, and it is part of the crate public interface
I thing adding it as a part of the public API might be for the best.
fixes: #3861
