Variable types - Perl example

Variables in Perl example from a Well House Consultants training course
More on Variables in Perl [link]

This example is described in the following article(s):
• Object Orientation in an hour and other Perl Lectures - [link]

Source code: henry Module: P301

#Each of the variable types illistrated in Perl:

# scalar - int, float, string, reference or regex
$abc = 14;
$abc = "kjadjkajklsdljksdjkljklsdfjlksdkljsdjksdf";
$hello_world = 6.7;
print ("sample $abc $hello_world\n");

# lists - an ordered collection of scalars
@peeps = ("Phil","Dan","Chris","Antonio");
print @peeps,"\n"; # List context
print @peeps + 0 ,"\n"; # Scalar context
print "@peeps\n"; # Double Quote context
print $peeps[2],"\n";

# Hashes - a keyed but unordered collection of scalars
%liveat = ("Leena" => "San Franciso",
        Pavol => "Acton",
        Michelle => "Uxbridge",
        Lee => "Harrow");
print %liveat,"\n";

# code - something that can be run such as a sub
sub set { print 42; return 54; }
print &set,"\n";
print set(),"\n";
print set,"\n"; # ONLY works because set already defined

# File handle - the structure used to access a file or other type of stream
open fh,"<","20101116_statlog.txt";
$lyne = <fh>;
print $lyne;

# Typeglob / applies a second (extra) name to ALL variables called "peeps"
*team = *peeps;
print "Our team includes @team\n";

__END__

wizard:lf graham$ perl henry
sample kjadjkajklsdljksdjkljklsdfjlksdkljsdjksdf 6.7
PhilDanChrisAntonio
4
Phil Dan Chris Antonio
Chris
MichelleUxbridgePavolActonLeenaSan FrancisoLeeHarrow
4254
4254
4254
000101 115453 3 11 _____.__W__C_....._.........K 0.85 0.50 0.40 904528 879256
Our team includes Phil Dan Chris Antonio
wizard:lf graham$

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