for(@a1=`cat file`;$a[0]=shift @a1;@a1)
{
  for(@a2=@b;$a[1]=shift @a2;@a2) # could be "for(;$a[1]=shift @b;@b)" if you don't care about emptying @b
  {
    for(@a3=grep /4/, @c;$a[2]=shift @a3;@a3)
    {
      <Statements>;
    }
  }
}

##</code><code>##

sub with {for (@{$_[1]}){$_[0] = $_;$_[2]();}}
sub in { \@_  } 
sub run(&) { $_[0] }

##</code><code>##

# parenthesis mandatory after in, bad idea after with and the commas can't be ommited
with $a[0], in(qw/Bonjour Bonsoir/), 
run {
    with $a[1], in ("Paul", "Jack", "Lord Voldemort"),
    run {
        say "@a";
    }; # semi-colon mandatory
}; # same here

##</code><code>##

Bonjour Paul
Bonjour Jack
Bonjour Lord Voldemort
Bonsoir Paul
Bonsoir Jack
Bonsoir Lord Voldemort