On Sat, Jun 25, 2022 at 09:08:30PM -0400, Wietse Venema <wie...@porcupine.org>
wrote:
> raf:
> > If .= can reliably distinguish between being applied to
> > a list or scalar parameter, maybe it could automatically
> > include a leading space when adding to lists.
>
> Unfortunately, the main.cf parser does not know if a parameter value
> is used as a list such as
>
> export_environment = TZ MAIL_CONFIG LANG
> export_environment .= NAME=value
>
> with intended result:
>
> export_environment = TZ MAIL_CONFIG LANG NAME=value
>
> and when a parameter is not:
>
> syslogname = ${multi_instance_name?{$multi_instance_name}:{postfix}}
> syslogname .= /$service_name
>
> with intended result:
>
> syslogname = ${multi_instance_name?{$multi_instance_name}:{postfix}}/blah
>
> Even if the main.cf parser wree made list aware, the value from one
> parameter can be substuted into another parameter value, i.e. list
> and non-list parameter values can be combined. It's better not to
> try to make the main.cf parser smart about list and non-list contexts.
>
> Wietse
I thought that might be the case. I also thought of a
,= alternative but as Viktor says, string append isn't
useful enough, and you'd want there to be a good case
for adding both operations.
Also, is .= the best notation? Would += be better? I
just ask because . and .= are Perl operators for string
concatenation/appending (so it makes perfect sense to
those who are lucky enough to know Perl), but + and +=
might be more natural for those who only know other
programming languages.
cheers,
raf
