*FOO = \"bar";

##</code><code>##

use constant FOO => "bar";

##</code><code>##

*FOO = \"BAR";
print qq(\$FOO is set to "$FOO"\n);

use constant FOO => "BAR";
print qq(Constant "FOO" is set to ) . FOO . qq(\n);

##</code><code>##

use constant FOO => "BAR";
print "The value of FOO is $FOO\n";