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

##</code><code>##

foo(sub { ... });

##</code><code>##

use strict;
use warnings;

sub my_map(&@) {
    my $cb = shift;
    my @rv;
    push @rv, $cb->($_) for @_;
    return @rv;
}

sub map_tester {
   print("pre\n");
   map { print("in\n"); return 1 } 1;
   print("post\n");
}

sub my_map_tester {
   print("pre\n");
   my_map { print("in\n"); return 1 } 1;
   print("post\n");
}

map_tester();
print("\n");
my_map_tester();

##</code><code>##

pre
in

pre
in
post

##</code><code>##

my @anon_list;
for (@a) {
    push @anon_list, foo();
}
@b = @anon_list;