Okay. I did see the function call, but assumed that the function would return an overloaded blessed reference (as new() in my example does), and then overloading would then come into play to determine the appropraite context.
It will be interesting to see if Want can detect/supply the calling context more quickly than the overloading. The latter is notoriously slow, but when I played with Want many moons ago, it was also pretty slugish. You might be able to avoid some of that if you c&p the logic directly into your own XS code I suppose?
Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
"Science is about questioning the status quo. Questioning authority".
In the absence of evidence, opinion is indistinguishable from prejudice.
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It will be interesting to see if Want can detect/supply the calling context more quickly than the overloading. The latter is notoriously slow...
The way I understand things, overload stuff is called from the code that interprets the de-referencing opcodes, individually in all five(?) cases. If it's slow, that's probably not because it has to determine the kind of reference needed, it should know. Not that it cared anyway.
...c&p the logic directly into your own XS code I suppose?
That is the plan.
Anno
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... overload stuff is called from the code that interprets the de-referencing opcodes ... If it's slow, that's probably not because it has to determine the kind of reference needed,
Exactly. It knows what it's got to do. It only needs to chase a few pointers in magic to find the callback--and still it is notoriously slow.
A cursory peek at want.xs shows an aweful lot of logic, including several physically and logically nested loops tracing opcode trees. I won't pretend to have understood half of what I saw in there, but it looks expensive, which supports my findings from a while ago.
My point is that it might be faster, and simpler, to have gimme_a_ref() return a ref blessed into a package that overloads the dereference operators. Especially as Alter is already using (as far as I understood your other thread), two levels of inside-out-style dereferencing which is already slow.
Additionally, what happens if someone assigns the return from gimme_a_ref() to a scalar, and then attempts to dereference it later? You'll have no applicable 'current context' at the time of the call from which to determine what use will be made of what you return.
Admittedly that can be addressed through documentation, but you'll be denying flexibility. You'll also create the situation of requiring the additional overhead of determining the calling context for every use.
Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
"Science is about questioning the status quo. Questioning authority".
In the absence of evidence, opinion is indistinguishable from prejudice.
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