m/\A\[_\p{ID_Start}]\p{XID_Continue}*\z/

##</code><code>##

use utf8;
binmode STDOUT, ':utf8';

no strict 'refs';
my $symbol = '£1%^@"¥';

$$symbol = 42;

print "\$$symbol = $$symbol\n";
print "$symbol is found in package ", *{__PACKAGE__ . '::£1%^@"¥'}{PACKAGE}, "\n";
print "\$main::${symbol} has a value of ", ${'main::£1%^@"¥'}, "\n";

##</code><code>##

(define ¥ (lambda (x y) (+ x y)))

;Value: |â¥|

1 ]=> (¥ 3 5)

;Value: 8