Current the function is defined as:

fnfrom_args(command_name:&[&str],args:&[&str]) ->Result<Self,EarlyExit>;

This could be changed to:

fnfrom_args<T,U>(command_name:&[T],args:&[U]) ->Result<Self,EarlyExit>whereT:AsRef<str>,U:AsRef<str>;

I think this is backward-incompatible because of type deductions that could now fail.

FromArgs::redact_arg_values should also be updated if this is done.

Why ?

Current when getting arguments fromstd::env::args_os(), severalcollects and transformations are necessary to go fromIterator<Item = OsStr> to&[&str], which is a little sad.

1. OsStr toString (to_string_lossy,to_string + unwrap)
2. Collect to a vec ofString
3. Iter,as_str
4. Collect to a vec of&str

With the change proposed in this issue, steps 3 and 4 would become unnecessary