[Omaha.pm] Is this necessary? (perl code)

James Harr jharr at ist.unomaha.edu
Thu Dec 11 14:13:42 PST 2008

iirc, @{} is an array dereference. Forced array casting is done by enclosing the function call in parenthesis. 

$arr_ref = [1,2,3,4];
print $arr_ref->[1]; # grab a single item; prints "2"
@arr_copy = @$foo;   # de-reference the whole thing to make a copy
@arr_copy = @{$foo}; # same, but more explicit way
@rv_copy = @{$obj -> method()}; # We have to do this to get the order of operations right.

sub method { return [1,2,3,4] }

The same goes for hash %{} and scalar ${} de-referencing.
$scalar = 42;
$scalar_ref = \$scalar; # Perl's scalar references are funny

James Harr <jharr at ist.unomaha.edu>
Assistant Research Systems Manager 
College of Information Science and Technology
University of Nebraska at Omaha

From: omaha-pm-bounces+jharr=ist.unomaha.edu at pm.org [mailto:omaha-pm-bounces+jharr=ist.unomaha.edu at pm.org] On Behalf Of Jay Hannah
Sent: Thursday, December 11, 2008 10:11
To: Justin Esbenshade
Cc: omaha-pm at pm.org
Subject: Re: [Omaha.pm] Is this necessary? (perl code)

I think @{ } is redundant with the fact that 
   my ($response, $success) = 
should put forward() into array context anyway. 
(Presumably forward() is using wantarray (perldoc -f wantarray) to determine what it should return based on the requested context.)
Try removing @{ } and then test both success ($twig, 1), and failure (0) returns from forward() to see if everything downstream from that code survives...  :)
From: Justin Esbenshade
Sent: Thu 12/11/2008 9:34 AM
     my ($response,$success) = @{$c->forward('OWS', 'CreateBooking', [ $room_args ])};
Is the @{ } required around the method call?  The few pages I saw from a Google search did not have that.
We're getting a Phoenix Fatal Error that's occurring saying we Can't use string ("0") as an ARRAY ref

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