Support alternative name/value separator

[epage]

Please complete the following tasks

• I have searched the discussions
• I have searched the existing issues

Clap Version

master

Describe your use case

A part of supporting non-unix syntax (#2468) is supporting a custom name/value separator.

Example:

icacls <filename> [/grant[:r] <sid>:<perm>[...]] [/deny <sid>:<perm>[...]] [/remove[:g|:d]] <sid>[...]] [/t] [/c] [/l] [/q] [/setintegritylevel <Level>:<policy>[...]]

Describe the solution you'd like

1. Come up with a name for this separator
2. Add a use_<name>, requires_<name>, and <name>_delimiter like use_delimiter, requires_delimiter, and value_delimiter
3. Deprecated requires_equals in favor of requires_<name> (especially since it references a specific syntax)
4. Rename use_delimiter to use_value_delimiter and requires_delimiter to requires_value_delimiter to disambiguate

Alternatives, if applicable

No response

Additional Context

No response

[mkayaalp]

1. Come up with a name for this separator

I don't think we'll be able to come up with anything that does not include the word "separator" in it and calling it simply the separator would be no better than calling the other one simply the delimiter. So, I think you got in the title. I vote name_value_separator. It does separate the name and the value from each other after all.

4. Rename use_delimiter to use_value_delimiter and requires_delimiter to requires_value_delimiter to disambiguate

Agreed. It parallels value_terminator.