[Haskell-cafe] Template Haskell messes up scoping?

Martijn van Steenbergen martijn at van.steenbergen.nl
Sun Mar 29 14:34:33 EDT 2009

Hi Stephan,

Stephan Friedrichs wrote:
> Hi,
> when I tried to reorganize some code to use the data-accessor and
> data-accessor-template packages, i stumbled across a strange effect:
> When using template haskell some things are out of scope that really
> shouldn't be.

Apart from the specific problematic file you gave, I had some other 
scoping issues when using TH to generate the accessors. I worked around 
this by defining my data types in a separate module Types and calling 
the TH functions in that module as the last lines. Then I had my other 
modules import Types, bringing the types and the accessors back in 
scope. See:


Hope this helps,


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