I'm not sure exactly what you're going for, but maybe this helps: 

Win8 Strawberry 5.8.9.5 (32)  Sun 11/22/2020  1:19:09
C:\@Work\Perl\monks
>perl
use strict;
use warnings;

use constant INVALID_DATA => ( q{invalid}, 0 );
use constant ADD_DATA => ( q{add}, 1 );
use constant REMOVE_DATA => ( q{remove}, 2 );
use constant MODES => ( \&ADD_DATA, \&REMOVE_DATA );

warn((ADD_DATA)[0]);
warn((ADD_DATA)[1]);

warn((MODES)[0]);
warn((MODES)[1]);

warn((MODES)[0]->());
warn((MODES)[1]->());
^Z
add at - line 11.
1 at - line 12.
CODE(0x1d2be34) at - line 14.
CODE(0x1cf904c) at - line 15.
add1 at - line 17.
remove2 at - line 18.

[download]
(Update: Also works under Perl version 5.30.3.1 64-bit.)

Update 1: Changed example code above: removed unused use Data::Dumper; statement.

Update 2: The syntax &{(MODES)[0]} also works, and you may consider it more elegant: 

Win8 Strawberry 5.8.9.5 (32)  Sun 11/22/2020  1:34:08
C:\@Work\Perl\monks
>perl
use strict;
use warnings;

use constant ADD_DATA    => qw(add    1);
use constant REMOVE_DATA => qw(remove 2);
use constant MODES       => (\&ADD_DATA, \&REMOVE_DATA);

warn &{(MODES)[0]};
warn &{(MODES)[1]};
^Z
add1 at - line 8.
remove2 at - line 9.

[download]
Also works under version 5.30.

Give a man a fish:  <%-{-{-{-<

In reply to Re: Multi-dimensional constants (updated) by AnomalousMonk
in thread Multi-dimensional constants by Ionic

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