no strict qw(refs);
my $variable = 'host_mail';
my ${ $variable } = '80.80.80.80';

##</code><code>##

no strict qw(refs subs);
my $variable = host_mail;
my ${ $variable } = '80.80.80.80';

##</code><code>##

my ${ host_mail } = '80.80.80.80';

##</code><code>##

my $scandal_topic = 'email';
say "We will call this scandal '${scandal_topic}gate'!";
# says "We will call this scandal 'emailgate'!";

##</code><code>##

my $scandal_topic = 'email';
say "We will call this scandal '$scandal_topicgate'!";
# dies "Global symbol "$scandal_topicgate" requires explicit package name