[m-dev.] dummy types and user defined equality

[Zoltan Somogyi]

On 06-Mar-2006, Julien Fischer <juliensf at cs.mu.OZ.AU> wrote:
> Do we consider dummy types, defined as below to be discriminated unions,
> or are dummy types not allowed to have user-define equality?

We haven't explicitly considered the issue. However, I am strongly included
to view that (a) any type that has user-defined equality shouldn't be
considered by the compiler to have a dummy type; and (b) any user who
adds user-defined equality to a type with only one value should have
their head examined.

Zoltan.
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