I think I need to call Getopt::Long twice. The first time I take from user the name of the configuration file (say --config abc). Then I read the file, and create a hash of parameters.

Then, as a 2nd pass, I need to overwrite any of these parameters in the config with user-specified values from the command line for this particular run. The config hash is too nested, so I just can't pass it to Getopt (like it is mentioned in the doc).

And so I resort to this:

use Getopt::Long;
my $configfile;
my @ARGVcopy = @ARGV; # because 1st pass eats all options in @ARGV!!
{
  local $SIG{__WARN__} = sub { }; # don't complain when see options re
+levant to the 2nd pass
  Getopt::Long::GetOptions('--config=s', \$configfile); # no check! it
+ will fail
}
die "config needed" unless $configfile;
my $confighash = parse_configfile($configfile);
# 2nd pass with restored ARGV
@ARGV = @ARGVcopy;
Getopt::Long::GetOptions(
 'config=s' => \my $dummy, #<<<< this belongs to 1st phase but is stil
+l in cmdline (@ARGV)
 '--max-value=i' => \$confighash->{'a'}->{'b'}->{'max-value'},
) or die "error cmd line params";
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Is there a more elegant way? I mean 2 passes, and then the $dummy? Modifying @ARGV between 1st pass and 2nd pass is not acceptable as a new can of worms will be opened (edit: or is it a question of 2 shifts?).

bw, bliako