Tuples in Haskell always have annoyed me a bit since each tuple of different dimension is hardcoded (I guess compilers enforce a maximum dimension on tuples?)<div><br></div><div>Since a tuple represents a fixed size data structure with different types at each coordinate, it feels as it should be possible to have a couple of type and data constructors to build a tuple, and to use recursion at the type level to have functions operate on tuples of any dimension.</div>
<div><br></div><div>E.g. one could then have a tmap function that takes a tuple of functions and a tuple of values and applies the function at coordinate N to the value at coordinate N.<br></div><div><br></div><div><div>Is something like this possible today in Haskell, e.g. using new features like type families, GADTs, template haskell, etc? Or do we need dependent types for it?</div>
<div><br></div><div>In C++x0 I believe it is now possible to do so, since they even allow a variable number of template arguments, using recursion at compile time (see e.g.&nbsp;<a href="http://publib.boulder.ibm.com/infocenter/comphelp/v9v111/index.jsp?topic=/com.ibm.xlcpp9.aix.doc/standlib/header_tuple.htm">http://publib.boulder.ibm.com/infocenter/comphelp/v9v111/index.jsp?topic=/com.ibm.xlcpp9.aix.doc/standlib/header_tuple.htm</a>&nbsp;)</div>
</div><div><div><div><br></div><div>Grapefruit has something like first class records, so I guess it should be possible (and simpler) to do this for tuples?</div><div><br></div><div><br></div><div><br></div><div><br></div>
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