Hash Lookup

A hash maps keys to values, and a lookup reads the value for one key.

hash_lookup.pl

use strict;
use warnings;

my %scores = (
    perl => 95,
    go   => 88,
    ruby => 91,
);
my $key = ;
my $value = $scores{$key};
my $found = exists $scores{$key} ? "yes" : "no";

print "key=$key\n";
print "found=$found\n";
print "value=$value\n";

use strict;
use warnings;

my %scores = (
    perl => 95,
    go   => 88,
    ruby => 91,
);
my $key = ;
my $value = $scores{$key};
my $found = exists $scores{$key} ? "yes" : "no";

print "key=$key\n";
print "found=$found\n";
print "value=$value\n";

use strict;
use warnings;

my %scores = (
    perl => 95,
    go   => 88,
    ruby => 91,
);
my $key = ;
my $value = $scores{$key};
my $found = exists $scores{$key} ? "yes" : "no";

print "key=$key\n";
print "found=$found\n";
print "value=$value\n";

hash lookup A hash lookup uses a key inside braces to read one stored value.