[perl #61610] Something is inconsistent with the undef warnings of .reduce

[Carl Mäsak]

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<moritz_> rakudo: say (1..10).reduce({$^a + $^b + $^c})
<p6eval> rakudo 34244: OUTPUT[Use of uninitialized value␤55␤]
<PerlJam> that's interesting
* PerlJam is looking at the code now
<masak> PerlJam: are you also submitting a rakudobug? otherwise I am.
<PerlJam> go ahead
* masak submits rakudobug
<eric256> whats the bug?
<masak> eric256: the "Use of uninitialized value" warning above.
<moritz_> masak: maybe that's because it just doesn't work to reduce a
list of every possible size with a three-arg function?
<eric256> but it was unitiliazed
<masak> moritz_: yes, now that I look at it, I think so too.
<masak> eric256: what was?
<PerlJam> still a bug though
<PerlJam> (IMHO)
<eric256> $^b and $^c for the last run
<masak> PerlJam: aye, it shouldn't warn, methinks
<masak> eric256: you're right.
<PerlJam> yeah, it pushes an appropriate number of undef to fill out
the arity of the sub.
<eric256> rakudo: list(1).reduce( { $^a.say; $^b.say;});
<p6eval> rakudo 34244: RESULT[1]
<rjh-> how else would you handle it?
<eric256> ohh but that should have the same error then
<eric256> rakudo: list(1).reduce( { $^a + $^b;});
<p6eval> rakudo 34244: RESULT[1]
<eric256> rakudo: list(1).reduce( { $^a + $^b + $^c;});
<p6eval> rakudo 34244: RESULT[1]
<eric256> rakudo: list(1,2).reduce( { $^a + $^b + $^c;});
<p6eval> rakudo 34244: OUTPUT[Use of uninitialized value␤]
<eric256> okay thats a bit weird
<masak> something inconsistent is going on.