Re: Unit unboxed tuples

On Sat, Dec 24, 2011 at 7:15 AM, Duncan Coutts wrote:

On 23 December 2011 20:09, Stefan Holdermans wrote:

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Here are the kinds of the type constructors:

                (,,) :: * -> * -> * -> *                 (,) :: * -> * -> *                 () :: *

                (# ,, #) :: * -> * -> * -> #                 (# , #) :: *  -> * -> # BUT                 (#  #) :: * -> #

Just of out curiosity, what would be a compelling use case for singleton and unit unboxed tuples?

For singleton unboxed tuples, any situation where you want to return a single value but not force its evaluation. This occurs for example with some low level functions in the implementation of ordinary lazy arrays.

How is that different from returning a normal value? -- Dave Menendez http://www.eyrie.org/~zednenem/