On Wed, Oct 15, 2008 at 6:05 AM, <[EMAIL PROTECTED]> wrote: > > Regarding existentials, the web page > http://okmij.org/ftp/Computation/Existentials.html > > demonstrates how to systematically eliminate existentials. In fact, > the object encoding via existentials can be easily transformed into > the encoding that uses only simple, first-order types. The web page > begs a question if there is ever any real need for existentials.
We might justify existential types on performance grounds. Stream fusion, for example, uses existentials to replace recursive types and functions with non-recursive types and functions, which are simpler to optimize. -- Dave Menendez <[EMAIL PROTECTED]> <http://www.eyrie.org/~zednenem/> _______________________________________________ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
