My question is quite simple, but unfortunately I can't resolve it:

I'd like to use a command line option with- or without an argument as a flag:

if it has an argument then the value of my scalar should be the argument, otherwise its value should be the default value. The command line may contain other arguments and I'd like to keep the @ARGV untouched.

I've started to play with the Getopt::Long modul and felt myself very close to the solution, but unfortunately it wasn't perfect:

use Getopt::Long;
#my $foo = 1;

GetOptions ('foo=s', \$foo);

print "foo: $foo\n" if $foo;

print "Unprocessed by Getopt::Long\n" if $ARGV[0];
foreach (@ARGV) {
  print "$_\n";
}

[download]

eg.:
>perl test.pl something -foo "my argument"
works fine, but
>perl test.pl something -foo
results a message: "Option foo requires an argument", even if you added a default value for your option in the code (see the commented line). (The GetOptions ('foo:s', \$foo) with the : type) doesn't drop error message, but the $foo has no value at all.) What I wanna reach is $foo with the default value (without error message) or $foo with the value if there is a value for -foo. Of course I no need the default value if there isn't the -foo argument in the command line at all.

I found a quite similar problem in between the recent nodes: Requiring option values in Getopt::Long, but there is no solution for my problem...

Thanks in advance

In reply to command line option with- or without argument by Vasek

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