Collection of collections (i.e. 2D array)

More than Simple Lists and Hashes! example from a Well House Consultants training course
More on More than Simple Lists and Hashes! [link]

This example is described in the following article(s):
• Take the dog on a lead - do not carry her. Perl references. - [link]

This example references the following resources:
http://www.wellho.net/data/requests.xyz

Source code: d3 Module: P217

# Collection of collections (i.e. 2D array)

$wurked = open FH,"<","requests.xyz";
# data file may be downloaded from http://www.wellho.net/data/requests.xyz
print "That was $wurked status\n";

# \n on end of die string supresses line number
$wurked or die "Unable to open input fyle\n";

# %staff is a hash

# Within it, the name @things is used to create lists; the name
# @things is TEMPORARY - it's lost at the } of the block, but the
# memory remains allocated because by that time it's a part of the
# %staff hash too.

while ($applicant = <FH>) {
        my @things = split(/\s+/,$applicant);
        $name = shift(@things);
        $staff{$name} = \@things;
        }

# Row by row access

foreach $person(keys %staff) {
        print "Application from \u$person ... ";
        @skills = @{$staff{$person}};
        print "(s)he knows @skills\n";
        }

# Element by element access ...
# All of the following do the same thing:

print "Ed's second skill is ",${$staff{"ed"}}[1],"\n";
print "Ed's second skill is ",$staff{ed}->[1],"\n";
print "Ed's second skill is ",$staff{ed}[1],"\n";

__END__

Sample output:

munchkin:ps11 grahamellis$ perl d3
That was 1 status
Application from Ulsyees ... (s)he knows Java PHP Perl
Application from Tommy ... (s)he knows Perl Java XML
Application from Quentin ... (s)he knows Tcl/Tk Perl PHP Ruby
Application from Jenny ... (s)he knows XML Perl Ruby ASP
Application from Iris ... (s)he knows Perl MySQL Java Tcl/Tk
Application from Rita ... (s)he knows PHP ASP Ruby Perl
Application from Charles ... (s)he knows Perl Ruby MySQL Tcl/Tk
Application from Kerry ... (s)he knows Perl Tcl/Tk Ruby MySQL
Application from Queenie ... (s)he knows Ruby Perl ASP MySQL
Application from Xena ... (s)he knows Java Perl PHP ASP XML
Application from Ken ... (s)he knows Tcl/Tk Python Java Perl
Application from John ... (s)he knows PHP XML Java Perl
Application from Xavier ... (s)he knows PHP Java Perl
Application from Rupert ... (s)he knows Java Python MySQL
Application from Barry ... (s)he knows Python XML Java Perl PHP
Application from William ... (s)he knows Ruby Perl PHP
Application from Sally ... (s)he knows Tcl/Tk Perl XML MySQL
Application from Zoe ... (s)he knows Ruby ASP Perl PHP
Application from Ed ... (s)he knows Ruby Perl Java PHP
Application from Gloria ... (s)he knows XML Perl Tcl/Tk MySQL
Application from Morris ... (s)he knows Perl Java PHP Tcl/Tk
Application from Florence ... (s)he knows Ruby PHP Java ASP
Application from Len ... (s)he knows Perl Java MySQL Ruby
Application from Cherry ... (s)he knows Perl Java Ruby MySQL
Application from Barbara ... (s)he knows Tcl/Tk ASP Ruby Java
Application from Tina ... (s)he knows Tcl/Tk Ruby Java
Application from Ethel ... (s)he knows MySQL Perl Tcl/Tk ASP
Application from Steve ... (s)he knows Tcl/Tk Perl PHP Ruby
Application from Petra ... (s)he knows XML Tcl/Tk ASP Perl Ruby
Application from Yollanda ... (s)he knows Ruby MySQL Tcl/Tk
Application from Adam ... (s)he knows Tcl/Tk Perl Python MySQL
Application from Venus ... (s)he knows Java Perl Ruby ASP
Application from Zachary ... (s)he knows MySQL Java Tcl/Tk
Application from Graham ... (s)he knows Java Perl Tcl/Tk
Application from Ivan ... (s)he knows Ruby Java Perl Tcl/Tk MySQL
Application from Leane ... (s)he knows PHP Python ASP Perl Java
Application from Yuri ... (s)he knows XML PHP Perl Tcl/Tk
Application from Fred ... (s)he knows MySQL Perl Java XML
Application from Orpheus ... (s)he knows MySQL Ruby Tcl/Tk XML
Application from Nigel ... (s)he knows PHP Python Java Perl
Application from Nina ... (s)he knows Tcl/Tk Perl ASP Ruby
Application from Wendy ... (s)he knows Perl Tcl/Tk ASP MySQL
Application from Peter ... (s)he knows PHP Java Perl
Application from Hazel ... (s)he knows PHP Python Perl Ruby ASP
Application from Margaret ... (s)he knows XML Perl Ruby MySQL Tcl/Tk
Application from Antonia ... (s)he knows Perl XML PHP Tcl/Tk MySQL
Application from Victor ... (s)he knows Ruby Perl Tcl/Tk MySQL
Application from Olivia ... (s)he knows MySQL Python ASP PHP
Application from Delia ... (s)he knows XML PHP Java ASP
Application from Harry ... (s)he knows PHP Python Java
Application from Uva ... (s)he knows MySQL Perl Java PHP
Application from David ... (s)he knows Perl Tcl/Tk Java
Ed's second skill is Perl
Ed's second skill is Perl
Ed's second skill is Perl
munchkin:ps11 grahamellis$

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* Perl Programming
* Perl for Larger Projects
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* Learning to program in Perl
* Perl Programming
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