Fellow Monks,

How do you get the length of an array that is passed by reference to a subroutine?

In the program below, I pass the array @test_array which contains [1, 2, 3], [4, 5, 6] by reference to a subroutine test_function.

The expected result is 2 but I keep getting the error Can't use string ("1") as an ARRAY ref while "strict refs" in use at line 12.

use warnings;
use strict;
use feature qw/ say /;
use Data::Dumper;
$Data::Dumper::Indent = 0;

sub test_function {
    my $ref_array = @_;
    say Dumper (@_); # $VAR1 = [[1,2,3],[4,5,6]];
    say scalar @{ $ref_array }; # line 12
}

my @test_array = ([1, 2, 3], [4, 5, 6]);
&test_function(\@test_array);

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Gratias tibi ago
Leudwinus

In reply to Length of Array Passed as Reference by Leudwinus

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