$message = "Hello $name\n";
#. . . other code that does unrelated stuff . . .
$name = "Larry Wall";
print $message;

##</code><code>##

$message = "Hello $name\n";
#. . . other code that does unrelated stuff . . .
$name = "Larry Wall";
print eval $message;

##</code><code>##

$message = 'Hello $name\n';
#. . . other code that does unrelated stuff . . .
$name = "Larry Wall";
print eval $message;