How to create a Perl subroutine that accepts a block of code

Question

I have a set of subroutines that look like this:

sub foo_1($) {
  my $name = shift;
  my $f; 

  run_something();
  open($f, $name) or die (\"Couldn\'t open $nam         


        

Answer 1

You want the & prototype.

sub foo(&@) {
    my ($callback) = shift;
    ...
    $callback->(...);
    ...
}

makes

foo { ... } ...;

equivalent to

foo(sub { ... }, ...);