Re: How can I access package variables in a dynamic way

In my script I want to do something like ... $Person::address_$num

No, you don't :-) Full explanation at Why it's stupid to 'use a variable as a variable name'.

You almost always want a hash, or in this case an array, instead.

package Person;
our @addresses;

package main;
my @lines;
for my $i (0..$#Person::addresses) {
    push @lines, $Person::addresses[$i];
}
[download]

Comment on Re: How can I access package variables in a dynamic way Select or Download Code

Replies are listed 'Best First'.
Re^2: How can I access package variables in a dynamic way by bangor (Monk) on Feb 12, 2019 at 15:35 UTC
Thanks, but as I said I can't change the Person package right now. I know it's wrong but I'm stuck with it.	[reply]
Re^3: How can I access package variables in a dynamic way by haukex (Archbishop) on Feb 12, 2019 at 15:37 UTC
I can't change the Person package right now. I know it's wrong but I'm stuck with it. If that really, really, really is the case, then here's enough rope to shoot yourself in the foot. This uses a trick to make `$Person::addresses` an arrayref whose elements are aliases to the original variables, so that you can modify elements of the array to modify the original variables. Consider this monkey-patching the `Person` package. `$Person::addresses = sub{\@_}->( map { no strict 'refs'; ${"Person::address_$_"} } 1..3 );` [download]	[reply] [d/l] [select]
Re^4: How can I access package variables in a dynamic way by bangor (Monk) on Feb 12, 2019 at 15:43 UTC
Unfortunately yes it really is. That does look like a solution - thanks.	[reply]
Re^3: How can I access package variables in a dynamic way by Corion (Patriarch) on Feb 12, 2019 at 15:37 UTC
The best approach would be to create the appropriate hash yourself then: `my %foreign_variables = ( address_1 => \$Person::address_1, address_2 => \$Person::address_2, address_3 => \$Person::address_3, # ... );` [download]	[reply] [d/l]
Re^4: How can I access package variables in a dynamic way by bangor (Monk) on Feb 12, 2019 at 15:44 UTC
I do like this, but in my actual use case (which I didn't mention, sorry) I don't know how many $nums there will be.	[reply]
Re^5: How can I access package variables in a dynamic way by Corion (Patriarch) on Feb 12, 2019 at 15:47 UTC
Re^6: How can I access package variables in a dynamic way by haukex (Archbishop) on Feb 12, 2019 at 15:54 UTC