> incidentally, how do we feel about adding a rustfmt check to the CI(s)?
yes we should be doing that. you can send another pr that adds the check to the Ci
The lack of qualification caused odd errors such as:
```
use clap;
let foo = clap::value_t!(matches.value_of("foo"),i u32).unwrap(); # OK
lot bar = clap::value_t!(matches, "bar", u32).unwrap(); # Compile fail
```
but
```
use clap::value_t;
let foo = value_t!(matches.value_of("foo"),i u32).unwrap(); # OK
lot bar = value_t!(matches, "bar", u32).unwrap(); # OK
```
subcommands
This commit changes the internal ID to a u64 which will allow for
greater optimizations down the road. In addition, it lays the ground
work for allowing users to use things like enum variants as argument
keys instead of strings.
The only downside is each key needs to be hashed (the implementation
used is an FNV hasher for performance). However, the performance gains
in faster iteration, comparison, etc. should easily outweigh the single
hash of each argument.
Another benefit of if this commit is the removal of several lifetime
parameters, as it stands Arg and App now only have a single lifetime
parameter, and ArgMatches and ArgGroup have no lifetime parameter.
Args can now be added to custom help sections. This breaks up the builder pattern a little by adding help section declarations inline, but it's the most intuitive method and doesn't require strange nesting that feels awkward.
```rust
app::new("foo")
.arg(Arg::with_name("arg1")) // under normal headers
.help_heading("SPECIAL")
.arg(Arg::with_name("arg2")) // under SPECIAL: heading
```
Closes#805
This commit primarily changes to a lazy handling of POSIX overrides by
relying on github.com/bluss/ordermap instead of the old HashMap impl.
The ordermap allows us to keep track of which arguments arrived first,
and therefore determine which ones should be removed when an override
conflict is found.
This has the added benefit of we no longer have to do the bookkeeping to
keep track and override args as they come in, we can do it once at the
end.
Finally, ordermap allows fast Vec like iteration of the keys, which we
end up doing several times. Benching is still TBD once the v3 prep is
done, but this change should have a meaningful impact.
