the array (0, 1)

I think this might be the misunderstanding here: (0, 1) isn't an array, in this form it's a literal list. While you obviously use lists to populate arrays, arrays and literal lists behave differently in different contexts. For example, an array in scalar context returns its size, whereas a list returns its last value, and taking a reference to an array creates an arrayref, while taking a reference to a list works as follows.

What is going on here is that your sub foo is returning the list (0, 1), and the \ (backslash) referencing operator is "distributive" when applied to lists, meaning that \(0, 1) is the same thing as (\0, \1). So your assignment basically becomes my $var = (\0, \1);. Then, the Comma Operator in scalar context "evaluates its left argument, throws that value away, then evaluates its right argument and returns that value", which is why $var is being assigned \1.

You could do several things, as the other monks have shown: [foo()], return [0, 1], or also possible would be return \@array. However, note that \ has a special-case behavior which means that sub foo { my @array = (0,1); return @array }; my $var = \(foo()); would not work, as "\(@foo) returns a list of references to the contents of @foo, not a reference to @foo itself." (perlref).

Update: See also this recent thread, the FAQ What is the difference between a list and an array?, and perhaps one or two other PerlMonks threads such as What is the difference between a list and an array?.

In reply to Re: Reference to return value of a subroutine by haukex
in thread Reference to return value of a subroutine by Christina

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