> On 18 Jul 2019, at 17:42, Tom Lane <t...@sss.pgh.pa.us> wrote: > return > if (exists $oconf->{dow} > && grep { $_ eq $wday } @{ $oconf->{dow} }); > > I'm the world's worst Perl programmer, but isn't that backwards? > It seems like it will return undef if today matches any entry > of the dow list, making dow a blacklist of weekdays *not* to run > the step on.
As it’s in a scalar context, grep will return the number of times for which the condition is true against the list entries, so if $oconf->{dow} doesn’t have duplicates it will return 1 if $wday is found on the list. This will in turn make the condition true as the exists expression must be true for grep to at all execute. cheers ./daniel