[Haskell-cafe] An issue with EDSLs in the ``finally tagless'' tradition

[Luke Palmer]

On Wed, Sep 23, 2009 at 10:24 PM, Brad Larsen <brad.larsen at gmail.com> wrote:
> On Wed, Sep 23, 2009 at 11:12 PM, Luke Palmer <lrpalmer at gmail.com> wrote:
>> I would like to see an example of this unmodularity, making use of the
>> polymorphism, so I can understand what you're asking better.
>>
>> Luke
>
> [...]
>
> A simple test case, combining boolean expressions and arithmetic expressions:
>
>    test1 = cond (true &&* false)
>                 (pae_constant 0)
>                 (pae_add (pae_constant 22) (pae_constant 20))
>    -- unE test1 <===> 42

Looks great!  So, where is the modularity problem?

Luke