use strict;
use warnings;
use Class::Struct;              # include <structs>

struct( document => {
    fileID  => '$',             # $ = scalar = int
    filename => '@',            # @ = array (of char) = string
    tags => '@'                 # tags - array of strings
});

# all of these three attempts to allocate memory fail:
#my $doc = document->new( );     # produces: Can't locate object method "fileID" via package "doc" (perhaps you forgot to load "doc"?) at testsnippet01.pl line 18.
#my $doc = new( 'document');     # produces: Undefined subroutine &main::new called at testsnippet01.pl line 12.
#my $doc = new( document);       # produces: Bareword "document" not allowed while "strict subs" in use at testsnippet01.pl line 13.

my $doc = <WhatGoesHere?>        # Hopefully a Perl saint knows what goes here...

doc->fileID( 123 );
doc->filename( 'SampleFileName' );
doc->tags( 'tag1', 'tag2', 'tag3'  );

print "File ID:  ", doc->fileID, "\n";
print "Filename: ", doc->filename, "\n";
print "Tags:     ", doc->tags, "\n";