Pattern matching identical values
This is called a nonlinear pattern. There have been several threads on the haskell-cafe mailing list about this, not long ago. Here are two: http://www.mail-archive.com/[email protected]/msg59617.html http://www.mail-archive.com/[email protected]/msg62491.html Bottom line: it’s not impossible to implement, but was decided against for sake of simplicity. By the way, you do not need if or case to work around this; … Read more