sub vector {
    my ($aa) = @_;
    $aa->[0] = my $one;
    $aa->[1] = my $two;
    $aa->[2] = my $three;
    my $vector = V($one, $two, $three);
}

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In this function:

  1. The function is passed an array reference;
  2. The first three elements of the referent of this array reference are assigned the initial values (undef) of three newly-created lexical scalars;
  3. The values (all still undef) of these newly-created scalars are passed to the  Math::Vector::Real::V() function;
  4. The return value of the  V() call is assigned to a new lexical scalar  $vector (which immediately goes out of scope) and is also implicitly returned from the function call.
Does passing the scalar values of  $one $two $three (all undef) to  V() serve any purpose? Given that its argument parameters are always the same, can  V() ever return any differing value; i.e., is it an impure function?

I haven't examined Math::Vector::Real at all, but I would suspect things begin to go wrong within the  vector() call itself.

Give a man a fish:  <%-(-(-(-<

In reply to Re: How to vector by AnomalousMonk
in thread How to vector by jcklasseter

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