[Haskell] Extensible records: Static duck typing

Cale Gibbard cgibbard at gmail.com
Tue Feb 5 06:35:57 EST 2008

On 05/02/2008, Cale Gibbard <cgibbard at gmail.com> wrote:
> On 05/02/2008, Barney Hilken <b.hilken at ntlworld.com> wrote:
> >
> >         Should {label := "Hi", color := blue} and {color := blue, label :=
> > "Hi"} have the same type?
> >
> The scoped labels paper has an interesting feature in this regard:
> labels with different names can be swapped at will, but labels having
> the same name (which is allowed) maintain their order. The types are
> equivalent in either case though.

Er, sorry, no they're not. Two labels with the same name may have
different types, and you can't swap them at the type level either,

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