perl function keys

The keys function in Perl is used to retrieve a list of keys from a hash. It takes a single argument, which is the hash whose keys are to be retrieved.

Here's an example that demonstrates how to use keys:

#!/usr/bin/perl

use strict;
use warnings;

# Define a hash of key-value pairs
my %hash = (
    "foo" => 1,
    "bar" => 2,
    "baz" => 3,
);

# Get a list of keys from the hash
my @keys = keys %hash;

# Print the keys to the console
print "Keys: @keys\n";

In this example, we start by defining a hash with three key-value pairs. We then use the keys function to retrieve a list of keys from the hash. We assign this list to a variable called @keys.

We then print the keys to the console using print. The @keys array is interpolated into the string using the @ symbol, which expands the array into a space-separated list of its elements.

Note that the order of the keys in the resulting list is not guaranteed to be the same as the order in which they were added to the hash. Also note that the keys function only retrieves the keys from the hash, not the values.