This creates distinct tutorial examples from complex feature examples
(more how-tos). Both sets are getting builder / derive versions (at
least the critical ones).
This ports our example testing over to [trycmd](https://docs.rs/) so
we can:
- More thoroughly test our examples
- Provide always-up-to-date example usage
The old way of testing automatically picked up examples. This new way
requires we have a `.md` file that uses the example in some way.
Notes:
- Moved overall example description to the `.md` file
- I added cross-linking between related examples
- `14_groups` had a redundant paragraph (twice talked about "one and
only one"
This reverts commits 24cb8b1..d0abb37 from clap-rs/clap#1840
This is part of #16. clap-rs/clap#1840 wasn't the right call but we
don't have time to make the decision now, so instead of having one
option and changing it in 4.0, this reverts back to clap2 behavior.
This better models what users should be doing and makes it so all
comments are more clear. In a prior commit, when a changed an `exit` to
`unwrap`, I disliked the fact that I was mixing an unwrap explanatory
comment in with another comment. This makes them stand apart.
* feat(arg_value): ArgValue can be used for possible_values
Through the ArgValue it is possible:
* `hide` possible_values from showing in completion, help and validation
* add `about` to possible_values in completion
* Resolved a few change-requests by epage
* make clippy happy
* add ArgValue::get_visible_value
* remove verbose destructering
* rename ArgValue::get_hidden to ArgValue::is_hidden
* add test for help output of hidden ArgValues
* Documentation for ArgValue
There is an issue that required to implement From<&ArgValue> for
ArgValue. We should probably find a solution without that.
* fix requested changes by epage
* fix formatting
* add deref in possible_values call to remove From<&&str>
* make clippy happy
* use copied() instad of map(|v|*v)
* Finishing up for merge, hopefully
* changes requested by pksunkara
