Question

I want something like..

all_objects.pl

my $sub = $ARGV[1];
...

@objs = get_all_objects();
for my $obj (@objs) {
    // invoke subroutine $sub with param as $obj.   
}

now if I say

all_objects.pl "print 'x '" 

all_objects.pl "print '$_ '"

I should get

obj1 obj2 obj3 ...

i.e. the command line arg act as a subroutine in some way. Can this be achieved?

Answer 1

eval "" is bad. Use something like the following, if it fulfills your needs:

my ($sub) = @ARGV;

my %prepared = (
    print => sub { print "$_[0]\n" },
    woof  => sub { $_[0]->woof },
    meow  => sub { $_[0]->meow },
);

@objs = get_all_objects();
for my $obj (@objs) {
    $prepared{$sub}->($obj);   
}

Update: For debugging purposes, Perl has a debugger: perldoc perldebug