I just tried "empty @a" against my solution. The _ prototype forces scalar context on the first argument:

/opt/perl/bin/perl5.10.0 -M5.10.0 -e 'sub display(_){say $_[0]};@a=();
+display(@a);push@a,"x";display(@a)'

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Whether that is considered to be unintuitive or not depends on the user I guess

In reply to Re^2: Is it possible to write a sub that understand default variables ? by Corion
in thread Is it possible to write a sub that understand default variables ? by bcarnazzi

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