Question

• I have 5 Perl files that are verification scripts for 5 different states of my environment.

  Each of them has at least a couple of subroutines.

• Till now, the number of states was limited to 5 and these worked fine. But now, I have like 20 more states of the environment and hence 20 more Perl scripts according to the current design.

• I want to move all the five scripts to just one script which takes the state as an argument and have 5 different subroutines for 5 different states.

  This way, when I need to add a verify for yet another state, I will just have to define a new subroutine instead of a whole new Perl script.

• The problem is that it will mean using nested subroutines (which are known to run into issues), or unrolling the subroutines themselves.

For example,

original scripts

$ cat verify1.pl
sub a1 {
    ...
}
sub b1 {
    ...
}
a1(); b1(); a1();
$ cat verify2.pl
sub a2 {
    ...
}
sub b2 {
    ...
}
sub c2 {
    ...
}
a2(); b2(); c2(); a2();
$

consolidated script

$ cat verify.pl
sub one {
    ...
}
sub two {
    ...
}
my ($arg) = @ARGV;
if ($arg == 1) {
    one();  # should do what verify1.pl did
}
elsif ($arg == 2) {
    two();  # should do what verify2.pl did
}
$

What should I do to resolve this?

Answer 1

sub one {
    do 'verify1.pl';
}
sub two {
    do 'verify2.pl';
}

In the long run, however, it is better to convert your scripts into modules in order to manage the complexity in a modern and sane fashion.