Re: [Libguestfs] [PATCH v2 2/3] mllib: Use L"..." and S '...' for long and short options.
On Mon, Jul 18, 2016 at 05:40:11PM +0200, Pino Toscano wrote:
On Monday, 18 July 2016 14:43:03 CEST Richard W.M. Jones wrote:
> > > - let validate_key key =
> > > - if String.length key == 0 || key == "-" || key ==
"--"
> > > - || key.[0] != '-' then
> > > - invalid_arg (sprintf "invalid option key: '%s'"
key)
> > > + let validate_key = function
> > > + | L"" -> invalid_arg "Getopt spec: invalid empty
long option"
> > > + | L"help" -> invalid_arg "Getopt spec: should not
have L\"help\""
> >
> > Theoretically both Arg and the current Getopt allow applications to
> > provide an own handler for --help, instead of the built-in one.
>
> Sure, but I don't think that's a good idea :-)
Well, I could have avoided that when proposing the final Getopt patch...
Also, there should be the same checks for M"something" of the
L"something" ones.
How about I add this case:
let validate_key = function
+ | M s when String.length s <> 2 || (s.[0] <> 'i' && s.[0]
<> 'o') ->
+ invalid_arg "Getopt spec: invalid use of M\"...\" option - only use
this for virt-v2v -iX and -oX options"
| L"" -> invalid_arg "Getopt spec: invalid empty long option"
It effectively excludes any use of the M option except for the
special cases in virt-v2v.
> > IMHO it'd be better to sort the specs at this point,
like done before;
> > otherwise, --help (and potentially any non-hidden built-in option added
> > here) will be shown only at the end of the other specs.
>
> At the beginning of the list, and it was deliberate. However it's
> just a matter of preference, and the options could be sorted later.
Well I'd prefer it sorted, since it won't create arbitrary lines of
--help with different order, which look a bit odd.
OK, I changed the sort so it happens after the --help and other
options have been added.
Also, making everything ordered was basically the reason for the
helper
type t, and the mutable state of its specs field.
Indeed - I couldn't work out how to rewrite the code without
mutability.
Rich.
--
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
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