That definitely pushes me towards one of the "long" adoption paths. Here adding a Semigroup instance for Matrix actually works to get the same symbol, but it has a different fixity (infixr 8). Same with (<>) in the pretty printing libraries (infixl 6). In Data.Monoid and Data.Semigroup we have infixr 6 <> -Edward On Mon, Mar 30, 2015 at 2:51 PM, Henning Thielemann < lemming@henning-thielemann.de> wrote:
On Mon, 30 Mar 2015, Edward Kmett wrote:
Collapse the first two steps into one step, but this means that nobody
gets any warning of new names coming into the Prelude. On the other hand this would get us all the way to done by 7.14. On one hand, the first order consequence the amount of breakage caused by adding Semigroup to Prelude and taking (<>) is almost entirely confined to a handful of pretty printing libraries -- and we already broke those same libraries by taking (<$>).
Btw. hmatrix is another prominent package defining (<>) for matrix and related multiplications.