Existence error when executing Curry program
The program
double x = (x, x)
f (fst (double x)) = (x, True)
e = snd (f (failed :: ()))
leads to the error
ERROR: error(existence_error(procedure,/(unifEq,6)),context(/(blocked_hnf,4),_))
when e
gets executed in the REPL of the newest PAKCS version. However, this program does work with an older version.
Edited by Finn Teegen