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Possible bug with k and j
Hi! I've been working on my own little Funge-98 interpreter and I've been testing against other interpreters, including of course cfunge. In testing the k
instruction, I ran into a fair amount of undefined behaviour with different interpreters doing different reasonable things, but there's one thing that I think is a bug in cfunge in which iterating (k
) the jump (j
) instruction jumps too far.
To illustrate, this program:
332kjvvvvvvvvv @
123456789
>>>>>>>>> v
,a.,k7"2 * 3 = "< v
vvvvvvvvvvvvvvvjk3::4<@
fedcba9876543210
>>>>>>>>>>>>>>>> v
@,a.,k7"4 * 3 = "<
prints
2 * 3 = 7
4 * 3 = 14
in cfunge, but
2 * 3 = 6
4 * 3 = 12
in every other interpreter I've tried (rcfunge, fbbi, ccbi, pyfunge).
If you're interested, here's my larger “edge cases of k
’ test: https://github.com/tjol/rfunge/blob/f8a55e38be491e550e69d871a435004e8d58a176/tests/manual_tests/k.b98
[again, no pressure for you to actually spend any time on this if you have better things to do]
I don't have time to look at this right now, but do you happen to know if this is something tested by the Mycology test suit?
I don't have time to look at this right now, but do you happen to know if this is something tested by the Mycology test suit?
It's not.