[Haskell-cafe] Crash in GHCI - what is the correct behavior here?
divisortheory at gmail.com
Thu Mar 19 00:21:08 EDT 2009
Basically just learning haskell, I would have posted this in the beginners
list but since it involves a segfault of GHCI, I figured it might be worth
I was trying to get a good understanding of local variable scoping issues,
so I tried the following:
f :: (Num a) => a -> a
f x =
let p = x*x
let p = x*p
I have some background in ML, which led me to believe that what should
happen here is that the function would return x^3. Instead, GHCI just
completely terminates, I guess with a segfault. What's the "correct"
behavior here? Should it even compile? I understand that you can't
redefine the same symbol twice in the same scope, so I tried this
specifically to see what would happen if you defined the same variable again
in a nested scope. I thought it would just shadow the original declaration,
while still using the original p to calculate the value of the new p. I
don't think the problem is the re-declaration of the same symbol in a nested
scope (although if someone could clarify that would be nice), but rather the
fact that I've attempted to use the previous declaration of p in defining
the new declaration of p.
Would it be a safe assumption that a bug report should be submitted over
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