> But share some light, why is it working with @ARGV = @preserved; # restore original @ARGV?

I' dunno well your skills but if you have not understood what the venerable monk tobyink says below, and directly answering to your cited above assertion:

the <> diamond operators consumes @ARGV so if you save a safe copy in @preserved you can refill @ARGV when you need ie first line of the two subs in the tobyink's example above.

As said below the <> diamond can also feed @ARGV opening SDTIN as last resource, so the above works because it restores @ARGV original contents at the top of the two testing subs.

L*

There are no rules, there are no thumbs..
Reinvent the wheel, then learn The Wheel; may be one day you reinvent one of THE WHEELS.

In reply to Re^3: Benchmark diamond operator by Discipulus
in thread Benchmark diamond operator by thanos1983

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