#!/usr/bin/perl -w
use strict;

my $method = shift || 1;
my $filename = shift || 'other.pl';
my $sub = shift || 'hello';

if ($method == 1) {
    print "First method\n";
    {
    local $/;
    open OTHER, "< $filename" or die "can't open\n";
    my $other = <OTHER>;
    close OTHER;
    eval $other . ";$sub";
    }
}
elsif ($method == 2) {
    print "Second method\n";
    scalar eval `cat $filename`;
    eval $sub;
}
else {
    print "Third method\n";
    do $filename;
    eval $sub;
}

##</code><code>##

#cat other.pl

sub hello {
    print "hello world\n";
}

##</code><code>##

# cat other2.pl
sub hi {
    print "hi, world!\n";
}

##</code><code>##

$ perl test_runtime.pl 1 other.pl hello

##</code><code>##

$ perl test_runtime.pl 2 other2.pl hi
$ perl test_runtime.pl 3 other2.pl hi

##</code><code>##

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