Make TryFrom::try_from the default for try_from_os_str annotation

[aj-bagwell]

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• I have searched the discussions
• I have searched the open and rejected issues

Clap Version

3.1.6

Describe your use case

All the kinds that can be used with the parse annotation have a default except for try_from_os_str. I think the most logical default would be std::convert::TryFrom::try_from. There don't seem to be and types that implement TryFrom<&OsStr> in the standard library, but it is the most obviouse trait to implement for things like file names that take a path but may not be valid.

Describe the solution you'd like

use clio::{Input, Output}
struct Opt {
    /// Would like to be able to do this
    #[clap(parse(try_from_os_str))]
    in_file: Input,

    /// Instead of this
    #[clap(parse(try_from_os_str = Output::try_from))]
    out_file: Output,
}

Alternatives, if applicable

No response

Additional Context

No response

[epage]

While there might be a default for us to use, overall researching and deciding on this seems like a fairly low priority because try_from_os_str is a fairly low use case. The few people who use it can just specify it directly.

[epage]

With #3732, the parse attribute is being phased out in favor of value_parser,, so I'm closing this issue.