Interpreting the strictness annotations output by ghc --show-iface

Brandon Allbery allbery.b at
Thu Mar 8 01:38:24 CET 2012

On Wed, Mar 7, 2012 at 18:41, Johan Tibell <johan.tibell at> wrote:

> Edward, I have looked at that file before and it didn't make me much
> wiser, because I cannot map it to the output.
> I find it's the parenthesis that confuses me the most. What does this mean?
> C(U(LU(L)))

I think the original type signature is needed to figure it out.  In the
earlier example it indicated ghc drilling down into the type (a tuple) and
determining the strictness of the constituents.

brandon s allbery                                      allbery.b at
wandering unix systems administrator (available)     (412) 475-9364 vm/sms
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