From @hoelzro

When invoking callsame in add_method when making a custom metaclass, callsame fails to invoke the next candidate on even-numbered invocations. Adding an explicit return in front of callsame, or a statement after it (ex. say 'hi') fixes the issue. Please consult the attached code.

I dug into the callsame code a bit, and it seems that the same dispatcher object is used between calls. This causes the dispatcher to incorrectly think that it is out of candidates on odd-numbered invocations of callsame. I don't know how the dispatcher object is initialized; I would be happy to dig into this further if someone could point me in the right direction.

From @hoelzro

TestHOW.pm

From @hoelzro

test.p6

From @jnthn

On Thu, 07 May 2015 20​:30​:53 -0700, rob@​hoelz.ro wrote​:

When invoking callsame in add_method when making a custom metaclass,
callsame fails to invoke the next candidate on even-numbered
invocations. Adding an explicit return in front of callsame, or a
statement after it (ex. say 'hi') fixes the issue. Please consult the
attached code.

I dug into the callsame code a bit, and it seems that the same
dispatcher object is used between calls. This causes the dispatcher
to incorrectly think that it is out of candidates on odd-numbered
invocations of callsame. I don't know how the dispatcher object is
initialized; I would be happy to dig into this further if someone
could point me in the right direction.

This works now on HEAD, and just needs a test (which I believe is already being worked on).

The RT System itself - Status changed from 'new' to 'open'

From @jnthn

On Tue, 03 Jan 2017 10​:11​:23 -0800, jnthn@​jnthn.net wrote​:

On Thu, 07 May 2015 20​:30​:53 -0700, rob@​hoelz.ro wrote​:

When invoking callsame in add_method when making a custom metaclass,
callsame fails to invoke the next candidate on even-numbered
invocations. Adding an explicit return in front of callsame, or a
statement after it (ex. say 'hi') fixes the issue. Please consult
the
attached code.

I dug into the callsame code a bit, and it seems that the same
dispatcher object is used between calls. This causes the dispatcher
to incorrectly think that it is out of candidates on odd-numbered
invocations of callsame. I don't know how the dispatcher object is
initialized; I would be happy to dig into this further if someone
could point me in the right direction.

This works now on HEAD, and just needs a test (which I believe is
already being worked on).

Tested in S12-meta/classhow.t by dogbert17++; resolving.

@jnthn - Status changed from 'open' to 'resolved'