Hi Monks,

I'm writing a subroutine which takes a variable number of arguments.  Sometimes the 2nd argument is absent, and for simplicity/conciseness I was hoping to be able to just omit it from the sub call, but it looks as if I might need to explicitly specify '' for that argument.  Is that correct?  Check this code out:

test1('A1',,'A3','A4');
test1('B1','','B3','B4');

sub test1
{
        print "args=" . join(',',@_) . "\n";
        my ($arg1, $arg2) = (shift @_, shift @_);
        my @argrest = @_;
        print "arg1=$arg1, arg2=$arg2, argrest=@argrest\n\n";
}

[download]
The output is: 
args=A1,A3,A4
arg1=A1, arg2=A3, argrest=A4

args=B1,,B3,B4
arg1=B1, arg2=, argrest=B3 B4

[download]

As you can see, it looks as if the 2nd argument is completely ignored, unless I explicitly supply it.

Questions:

1. Why does the 3rd argument seem to be seen as the 2nd when the 2nd is omitted? (Please don't say "because the 2nd is omitted").

2. Will I really need to supply the 2nd argument as '' or is there a simple way to get omitted arguments to be recognised?

Thanks.

In reply to Omitted subroutine arguments by tel2

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