When I use a lexical (open $file, ...) I get undef into $_[0].

Well, if your calling code is something like 

my $file;
open $file, ...

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then $file is undef, and open changes its value to be a file handle - but since you haven't called the core open() yet, you still see the undef.

Perl 6 - second systems done right

In reply to Re: Override the open builtin globally by moritz
in thread Override the open builtin globally by ninuzzo

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