my $struct= {pointers=>[]};
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$#{$struct->{pointers}} = last element index of pointers<br>
@{$struct->{pointers}} = array
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$ptrs=[];
push @{$ptrs}=$newpointer;
$#{$ptrs}; last index
@{$ptrs}; array itself
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or did you mean something else?

i was wishing to make and array of the hash GrandFather posted. i mean, getting many of those structs with an index for each.

i was wishing to make ... many of those structs with an index for each.

Here is one way, using anonymous hash references (see perlreftut):

#! perl
use strict;
use warnings;

my $dimension = 3;      # change as needed
my @array;

push @array, { data => $_, pointers => [] } for (1 .. $dimension);

push @{ $array[0]->{pointers} }, ('hello world', 'the end is nigh', 't
+his is the end');
push @{ $array[1]->{pointers} }, ('so long', 'and thanks', 'for all th
+e fish', 42);
push @{ $array[2]->{pointers} }, (3.141592653589793, 'ciao!');

for my $struct (@array)
{
    print "\nData is ", $struct->{data}, ".\n";
    print 'There are ', scalar @{ $struct->{pointers} }, " pointers al
+located:\n";
    print "\t$_\n" for @{ $struct->{pointers} };
}
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See also: perldsc and perlref.

If your structs become too complex, it may be better to implement them as objects — see perlootut.

HTH,

Athanasius <°(((>< contra mundum

You'd need to take a reference (a hashref) to the %struct hash. E.g.

my %struct = (data => 1, pointers => []);
my $struct_ref = \%struct;
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Or, in a single step:

my $struct_ref = {data => 1, pointers => []};
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Note the reference is a SCALAR value (uses $ sigil). There's nothing special about using these in an array:

my @array_of_structs = (\%struct1, $struct2_ref, {data => 1, pointers 
+=> []});
push @array_of_structs, \%new_struct;
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Access the hash data like this:

my $first_data = $array_of_structs[0]{data};
push @{ $array_of_structs[2]{pointers} }, 'abc', 'def';
my $third_struct_second_pointer = $array_of_structs[2]{pointers}[1];
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At this point it would probably help to know a little more about the problem you are trying to solve, but the following example may be relevant.

use strict;
use warnings;

my @structs;
local $/ = '};';

while (my $struct = <DATA>) {
    my ($name, $data) = $struct =~ m/\bstruct\s+(\w+).+\bint\s*:\s*(\d
++)\s*;/s;
    my @strings = $struct =~ m/(?<={|;)\s*pointer:\s*"([^"]*)";/sg;

    next if ! defined $data || ! @strings;
    push @structs, {name => $name, data => $data, strings => \@strings
+};
}

for my $struct (@structs) {
    print <<STRUCT;
struct $struct->{name} {
    int: $struct->{data};
STRUCT
    print "    pointer: $_;\n" for @{$struct->{strings}};
    print "};\n\n"
}


__DATA__
struct first {
  pointer: "hello world";
  pointer: "the end is nigh";
  pointer: "this is the end";
  int: 23;
};
struct second {
  pointer: "Gidday";   int: 12;
  pointer: "the second struct is nigh";
  pointer: "in fact this is it";
};
struct third {int: 21; pointer: "When two is not enough, you need a th
+ird";};
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Prints:

struct first {
    int: 23;
    pointer: hello world;
    pointer: the end is nigh;
    pointer: this is the end;
};

struct second {
    int: 12;
    pointer: Gidday;
    pointer: the second struct is nigh;
    pointer: in fact this is it;
};

struct third {
    int: 21;
    pointer: When two is not enough, you need a third;
};
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