Re: ed -p '' errors, but shouldn't

[Antonio Diaz Diaz]

Alexander Jones wrote:
> We should also consider that Arg_parser (where the issue originates)
> is used by more than just ed. I use it for my personal C/C++ projects,
> and other consumers may need null-string arguments.

Glad to know that someone found Arg_parser useful. :-)

I wrote Arg_parser to only accept non-empty option-arguments because I have 
never found an use for empty option-arguments. (And nobody ever requested 
support for empty option-arguments in arg-parser-bug).

I have found just one POSIX utility that accepts an empty option-argument 
(join -e ""), and it does not seem to do anything useful. (It replaces empty 
fields with the empty string, changing nothing).

This said, I can easily extend Arg_parser to accept four types of 
option-arguments to cover all possibilities (if someone finds an use for 'yme'):
  no    = 'no argument'
  yes   = 'non-empty argument required'
  maybe = 'optional argument'
  yme   = 'argument required, but it may be the empty string'


Best regards,
Antonio.