[Haskell-cafe] Monomorphic let bindings and darcs

Brandon Moore brandon_m_moore at yahoo.com
Wed Jan 26 00:50:21 CET 2011

The darcs 2.5 package uses the flat -fglasgow-exts, so it picks up MonoLocalBinds. This causes quite a few errors.

The error messages are particularly bad in


there is code of the form

explicitlyPolyMorphicFun arg $- \local ->
    very long body
    let localdef = _ in
    more long body

where failure to generalize the inner let is reported
as insufficient polymorphism at the outer annotation.

Glancing over the paper, it seems like the specific
problem is just deferring equality constraints between
ground types. Can't that be handled with a notion
of constrait normalization?


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