Unlike the previous ArgGroups, which made all args in the group mutually exclusive, one can now use
`ArgGroup::multiple(true)` which allows using more than one arg in the group (i.e. they're not all
mutually exclusive). When combined with `ArgGroup::required(true)` this effectively says, "At least
one of the args must be used, and using morethan one is also OK."
Closes#533
One can now use `AppSettings::DontDelimitTrailingValues` to stop clap's default behavior of
delimiting values, even when `--` or `TrailingVarArg` is used. This is useful when passing other
flags and commands through to another program.
Closes#511
Color are now only used when outputting to a termainal/TTY. There are three new settings as well
which can be used to control color output, they are:
* `AppSettings::ColorAuto`: The default, and will only output color when outputting to a terminal or TTY
* `AppSettings::ColorAlways`: Outputs color no matter where the output is going
* `AppSettings::ColorNever`: Never colors output
This now allows one to use things like command line options, or environmental variables to turn
colored output on/off.
Closes#512
For example, if an arg is part of a required group, it will only appear
in the group usage string, and not in both the group as well as the arg
by itself.
Imagine a group containing two args, `arg1` and `--arg2`
OLD:
`myprog <arg1> <arg1|--arg2>`
NEW:
`myprog <arg1|--arg2>`
Closes#498
Tons of code has been moved into functions, deduplicated, made much
easier to read, maintain, and understand. Comments still need to be
added, but that will happen shortly. Modules have also been moved around
to follow Rust conventions and best practices.
All functionality remains exactly the same
