The problem here is that open has a prototype, so it puts the @$_ in scalar context instead of interpolating it into the argument list.

For normal routines that can be circumvented by calling it with an ampersand, &yourroutine(@$_). Unfortunately I don't know how that works with open, neither &CORE::open(@$_) nor &open(@$_) work.

Perl 6 solves this problem by introducing a new syntax for explicitly interpolating arrays and hashes into argument lists, there it would be spelled open |@argumentlist.

Perl 6 - second systems done right

In reply to Re: Pitfalls met while opening multiple files by moritz
in thread Pitfalls met while opening multiple files by foobarrior

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