Example perl Program to Read Variables File from REPORTER

# Skeleton REPORTER Perl script showing extraction of variables fed to program
# The variable file REPORTER generates will be the LAST argument
#
# Variables are stored in a hash '%vars', each entry in the hash contains
# {value} and {description}.
#
# e.g. If REPORTER has a variable 'FRED' with value '1' and description
# 'Example variable' you can get at the variable value and description using:
#
# $vars{FRED}->{value}
# $vars{FRED}->{description}
#
# Arguments
# =========
# 1: Variables file
#
# Miles Thornton 23/5/2002
#
%vars = ();

if ($#ARGV >= 0)
{
    open (VAR, "< $ARGV[$#ARGV]") or die "Error: Cannot open variable file";

    while ( <VAR> )
    {
        chomp;
        &get_var_from_string($_);
    }
}
else
{
    die "Error: No variable file on the command line\n";
}

#########################################################
# START OF YOUR PROGRAM
#
# e.g. loop over variables and save them to a file

open (SAVE, "> varfile") or die "Error: Cannot open variables file";

foreach $var (sort keys %vars)
{
    print SAVE "Variable $var value=$vars{$var}->{value} ",
               "desc=$vars{$var}->{description}\n";
}

close (SAVE);

# END OF YOUR PROGRAM
#########################################################

exit;


#   ===================
sub get_var_from_string
#   ===================
#
# Tries to read a variable from the variable file
#
{
    my $string = shift;

    my ($var, $val, $desc);

    if ($string =~ /VAR\s+(\w+)\s+
                    VALUE\s*=\s*['"](.*?)['"]\s*
                    DESCRIPTION\s*=\s*['"](.*?)['"]
                   /x)
    {
        $var  = $1;
        $val  = $2;
        $desc = $3;
    }
    elsif ($string =~ /VAR\s+(\w+)\s+
                       DESCRIPTION\s*=\s*['"](.*?)['"]\s*
                       VALUE\s*=\s*['"](.*?)['"]
                      /x)
    {
        $var  = $1;
        $val  = $3;
        $desc = $2;
    }
    elsif ($string =~ /VAR\s+(\w+)\s+
                       VALUE\s*=\s*['"](.*?)['"]
                      /x)
    {
        $var  = $1;
        $val  = $2;
        $desc = undef;

    }

    if ($var)
    {
        $var = uc($var);
        $var =~ s/\s+/_/g;

        if (exists $vars{$var})
        {
            $vars{$var}->{value}       = $val;
            $vars{$var}->{description} = $desc;
        }
        else
        {
            my $variable = {};
            $variable->{value}       = $val;
            $variable->{description} = $desc;

            $vars{$var} = $variable;
        }
    }
}