comment on

A constant is usually better than a variable:

use constant HAVE_XYZ => !!$ENV{USE_XYZ};
use if HAVE_XYZ, 'XYZ';
...
if ( HAVE_XYZ ) {
    XYZ::foo(...)
}
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At it means that the if (...) stuff will be optimized away entirely when it's false. Also it will protect against $HAVE_XYZ being accidentally changed half way through running the process. (Of course, sometimes you do wish to start using XYZ later on by changing the variable, but that's probably less common.)

toby döt ink

In reply to Re^2: Using perl module if env is enabled by tobyink
in thread Using perl module if env is enabled by ovedpo15

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