Re^3: GetOpt::Long usage style

I know this is ancient, but since it's high on the Google hit list, I wanted to mention one thing...

This very cool trick does not work for @arrays. :-(

This:

    use Getopt::Long;
    GetOptions(
       'single=s' => \(my $single = ''),
        'multi=s' => \(my @multi  = ()),
    );
[download]

does *NOT* DWIM. According to "perlref":

As a special case, "\(@foo)" returns a list of references to the contents of @foo, not a reference to @foo itself.

I tried all kinds of permutations, and the best I could come up with was:

    use Getopt::Long;
    GetOptions(
       'single=s' => \(my $single = ''),
        'multi=s' => do { use vars '@multi'; \@multi },
    );
[download]

which, isn't quite as clean, IMHO.

(It *DOES*, however, keep the variable declarations and command-line options on the same line, at least, so you don't have to make changes in multiple places when adding new options. *shrug*)

Comment on Re^3: GetOpt::Long usage style Select or Download Code

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Re^4: GetOpt::Long usage style (\my @a) by tye (Sage) on May 09, 2014 at 00:37 UTC
`use Getopt::Long; GetOptions( 'single=s' => \(my $single = ''), 'multi=s' => \my @multi, );` [download] If you want to provide a non-empty default value, one way is: `use Getopt::Long; GetOptions( 'single=s' => \(my $single = ''), 'multi=s' => grep { @$_ = ('a','b') } \my @multi, );` [download] - tye	[reply] [d/l] [select]
Re^4: GetOpt::Long usage style by demerphq (Chancellor) on Apr 11, 2016 at 17:22 UTC
Besides what tye said in Re^4: GetOpt::Long usage style (\my @a), you can just use an arrayref instead. Obviously the reference operator \ required for scalars can be omitted. `'multi=s' => (my $multi = [1..3]),` [download] Same for a hash/hashref. Admittedly it is not quite the same as what one would expect from `'multi=s' => (\my @multi = (1..3)),` [download] Which throws an error, which I think is arguably an error in Perl. BTW, sorry it took me so long to reply, and thanks for adding your point. --- $world=~s/war/peace/g	[reply] [d/l] [select]


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