Mario is the only Perl programmer I know who has used dualvar in production code

Well now you know two, because I delight in using dualvars for XS constants :-) 

use Fluent::LibFluentBit qw( FLB_LIB_NO_CONFIG_MAP );
say FLB_LIB_NO_CONFIG_MAP;
say 0+FLB_LIB_NO_CONFIG_MAP;

[download]
Output: 
FLB_LIB_NO_CONFIG_MAP
2

[download]

The great part is that when you pass them to XS functions, they pass the integer that XS is looking for, and when you dump those parameters to STDOUT or a logger, you get the constant name so you can understand what is going on.

In reply to Re^3: Hash value test of zero by NERDVANA
in thread Hash value test of zero by themcp

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