I have to say that Eigen would have hard time being prior art: http://okmij.org/ftp/Haskell/number-parameterized-types.html http://okmij.org/ftp/Haskell/number-

I have to say that Eigen would have hard time being prior art: http://okmij.org/ftp/Haskell/number-parameterized-types.html http://okmij.org/ftp/Haskell/number-parameterized-types.html It's from 2007 and I think it is older than Eigen.