GHC 7.0.4 recursion while trying to derive type

Bogdan Opanchuk mantihor at
Mon Jan 9 14:00:21 CET 2012

Hello Christian,

On Mon, Jan 9, 2012 at 11:31 PM, Christian Maeder
<Christian.Maeder at> wrote:
> We have also such (cruel) code using these extension.

I understand that this code is not very good; I am just learning
Haskell, and it is an experiment to see what its type system can

>> I cannot answer this, but our code also compiles with ghc-7.2.2 using a
>> lower context-stack (of 26).
> Apologies, I've just re-checked and noticed that our code changed and needs
> consistently -fcontext-stack=26 for ghc-7.2.2 and ghc-7.0.4 (and ghc-7.0.2).

I just tried compiling my code with ghc7.0.4 and stack size 100, and
it produces the same error. In fact, I would be surprised if it
helped, because I would expect either infinite recursion (when type
derivation fails) or successful compilation with some small stack size
(definitely less than 26). The latter is the case for ghc7.2.2, which
successfully compiles my code with stack size 3.

Best regards,

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