in reply to How does Math::GMP overload the assignment operator ?

Just a guess: did you check fallback ?

See overload#Copy-Constructor

UPDATE

Another guess: I look into the sources (Perl side only) and saw that Math::GMP overloads numification where Math::GMPz doesn't.

"0+"  =>   sub { $_[0] >= 0 ? uintify($_[0]) : intify($_[0]) },

Cheers Rolf
(addicted to the Perl Programming Language :)
Wikisyntax for the Monastery

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Re^2: How does Math::GMP overload the assignment operator ? (more guessing)
by syphilis (Archbishop) on Nov 08, 2020 at 08:48 UTC
    "0+" => sub { $_[0] >= 0 ? uintify($_[0]) : intify($_[0]) },

    I don't think it's related to my particular problem, but it's an interesting case.
    Which operator is being overloaded here ? Is it overloading 'int' ?
    I actually wonder if that's a useful feature, but I won't rush to an assessment on that until I've found out a bit more about it.

    Cheers,
    Rob
[reply]
[d/l]

      That is overloading numeric conversion.

      That sub will be called whenever an object is used in a context that expects a number.

[reply]
[d/l]
        That sub will be called whenever an object is used in a context that expects a number.

        The only way I can find of having that sub called is by doing int($obj).
        Do you have an example of another way ?

        On Windows (where sizeof(long) is 4): 
        C:\>perl -MMath::GMP -le "print int(Math::GMP->new(311) ** 100);"
385227681

        [download]
        Math::GMPz achieves the same result with: 
        C:\>perl -MMath::GMPz=":mpz" -le "print Rmpz_get_ui(Math::GMPz->new(31
+1) ** 100);"
385227681

alternatively:

C:\>perl -MMath::GMPz -le "$x = (Math::GMPz->new(311) ** 100) & 429496
+7295; print $x;"
385227681

        [download]
        though, in this very last example, $x is a Math::GMPz object, not an IV.

        Cheers,
        Rob
[reply]
[d/l]
[select]

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