Andrew Gaffney wrote:
>
> I'm trying to write a subroutine that takes two scalars and two arrays as
> parameters. I've
> read that if you try to do this in a function, both arrays will get combined within
> '@_'.
All the values, including the two scalars, will be combined in a single
list and be accessible through the @_ array.
> Instead, I want the subroutine to take two scalars and two array references. I will
> not be
> doing any modification of the array data in the subroutine, so it will be more
> effecient
> this way, anyway. I vaguely remember reading in Learning Perl (or maybe Programming
> Perl)
> that the subroutine can be defined something like:
>
> sub my_subroutine([EMAIL PROTECTED]@) {
>
> }
Yes. The perlsub.pod document which should be on your hard drive
contains a more complete explanation of how subroutines work in Perl.
> My syntax may be off. Someone please correct me if so. (Do I really need to say
> this?)
> Now, how do I get those values in the subroutine?
>
> sub my_subroutine([EMAIL PROTECTED]@) {
> my ($scalar1, $scalar2, $arrayref1, $arrayref2) = @_;
> }
Yes.
> Another thing, how do you access an array through a reference?
To access a complete array:
@$arrayref1
> I know you access a hash
> through a reference by doing '$hashref->{hashkey}' instead of just
> '$hashref{hashkey}',
> but I've never done it with arrays (never needed to).
To access an array element:
$arrayref1->[ 4 ]
> One more thing (I promise). Do I
> need to do anything special to pass arrays as references to the function, like this:
>
> my_subroutine $scalar1, $scalar2, [EMAIL PROTECTED], [EMAIL PROTECTED];
>
> or can I pass them without the '\'?
Without the '\'. perl uses the prototype ([EMAIL PROTECTED]@) to convert the arrays
to references.
John
--
use Perl;
program
fulfillment
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