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Postings from January 2011
On Monday 03 Jan 2011 17:51:08 Michiel Beijen wrote:
> Hi Sunita,
>
> On Mon, Jan 3, 2011 at 2:24 PM, Sunita Rani Pradhan
>
> <Sunita.Pradhan@altair.com> wrote:
> > How can I define default arguments in Perl subroutine? Can
> >
> > anybody explain with examples?
>
> Sure, the best thing to do is to use named arguments for a subroutine,
> by means of using a hash. This is in general better for any subroutine
> that uses more than one or two arguments, also because the syntax is
> self-explanitory. If you use named arguments you can also use the '||'
> operator to assign a value if you don't have one.
> For instance, think about a sub like below. If you don't pass the
> 'status' when adding a user (or if you pass an untrue value), it will
> default to 'active'.
>
> =item adduserfoo()
>
> Adds a user to the foo application.
> adduserfoo(
> email => 'joe@example.com',
> password => 'somepass',
> status => 'active', # default is active, possible
> values: active, inactive.
> );
>
> =cut
>
> sub adduserfoo {
> my ($param_ref) = @_;
>
> my $email = $param_ref->{email};
> my $password = $param_ref->{password};
> my $status = $param_ref->{status} || 'active';
>
> # do stuff which adds the user
> }
>
Your subroutine implementation and the example do not match. Either add {...}
around the subroutine parameters to make it an anonymous hash reference, or
(less preferably IMHO) convert $param_ref to my %params = @_ (and omit the
->).
Regards,
Shlomi Fish
> --
> Mike.
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Shlomi Fish http://www.shlomifish.org/
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