Re: overload conflict between * and *= (as an example)

Another workaround is:

package Value;
use overload fallback => 1;
[download]

The explanation can be found by reading the overload documentation. Pay special attention to the section entitled Copy Constructor.

Comment on Re: overload conflict between * and *= (as an example) Download Code

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Re^2: overload conflict between * and *= (as an example) by yogibimbi (Initiate) on Feb 27, 2012 at 17:24 UTC
yeah, this took care of it, thanks. I had read that part of the perldoc before, but I could not imagine how this could be relevant, but looking at the section again, lit the light for me;-) And any suggestion as to why the rather inconspicious and innocent `$test->{obj} = $N;` can screw up the entire short program? I guessed that, if Perl would consider the "=" overloaded, it had to work only on lvalues, but the offending $N here is a rvalue, so, why does this produce a reaction at all?	[reply] [d/l]
Re^3: overload conflict between * and *= (as an example) by tobyink (Canon) on Feb 27, 2012 at 18:13 UTC
The reason is that with numbers you can do this: `my $a = 1; my $b = $a; $a++; $b++; say $a; # says "2" say $b; # says "2"` [download] But if $a and $b are overloaded references to numbers, then they refer to the same object, so you've actually incremented the same object twice. $a and $b are both 3. Perl forces you to deal with (or at least acknowledge that you've thought about) this problem by in certain circumstances forcing you to provide an overload for "=".	[reply] [d/l]