Source-Changes-D archive

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Old Index]

Re: CVS commit: src/usr.bin/make



About optional arguments to modifiers, such as in ${VAR:U}:

Am 25.01.2024 um 20:54 schrieb Simon Gerraty:
> Is there perhaps a general statement somewhere (I may have missed it)
> that could cover all these and be cited to pedantic users?
> Eg to the effect of perhaps, unless stated otherwise arguments to
> modifiers are optional or can be empty.
>
> I don't think its there and is hard to word succinctly.

No, I searched through the manual page but didn't find one.

Also, there are so many syntactic quirks and edge cases in make that I
don't think there's an easy to grasp single-line statement that covers
them all. Due to this, I'd go with:

> .It Cm \&:U\| Ns Ar newval
> If the variable is undefined,
> .Ar newval
> (which may be empty) is the value.

Then, add the same wording to ':D' and maybe to ':N' (since ':N' is a
shortcut for the more common ':M*') but not to ':M' itself (as that
would always result in an empty string, making it uninteresting).

Roland



Home | Main Index | Thread Index | Old Index