The foreach statement

.

The foreach statement is a core Perl idiom. The foreach command executes a block of code for a set of scalars, as might be stored in a list.

For example the next code fragment checks that everybody produced their last homework.

  foreach $user (@users) {
        if (-e ``/home/$user/public_html/cgi-bin/hello_world.pl''){
            print ``Looks like $user did their homework\n'';
        }
        else {
            print ``Looks like $user did not do their homework\n'';
        }
  }

In this code the array ``@users'' contains a list of user names and the operator ``-e'' checks to see if a file exists. The scalar $user is assigned each element of the list in turn, which is then used in the loop.

One way of iterating over a hash is as follows:

foreach $key (keys %letters){
print ``The value of $key is $letters{$key} \n'';
}