Is there any way to use a “constant” as hash key in Perl?

Question

Is there any way to use a constant as a hash key?

For example:

use constant X => 1;

my %x = (X => \'X\');

The above code will cr

Answer 1

use constant actually makes constant subroutines.

To do what you want, you need to explicitly call the sub:

use constant X => 1;

my %x = ( &X => 'X');

or

use constant X => 1;

my %x = ( X() => 'X');