On Wed, Oct 12, 2011 at 03:55:43AM +0530, mukesh tiwari wrote:
Hello everyone I was going through this tutorial http://hunit.sourceforge.net/HUnit-1.0/Guide.html and just wrote some simple code but i am getting error
ghci>let test1 = TestCase (assertEqual " equal " 3 ( id 3 )) ghci>let tests = [ TestLabel "test 1" test1 ]ghci>runTestTT tests <interactive>:0:11: Couldn't match expected type `Test' with actual type `[Test]' In the first argument of `runTestTT', namely `tests' In the expression: runTestTT tests In an equation for `it': it = runTestTT tests
Could some one please tell me what is wrong with this code.
This is something you should be able to figure out yourself. The error message is actually quite good. It says that it expects 'tests' to have type 'Test', but it actually has type '[Test]'. We can see why it has type [Test]: it is defined as tests = [ TestLabel ... ] that is, a list with a single element. So why is its type *expected* to be 'Test'? Well, look at the type of runTestTT: runTestTT :: Test -> IO Counts It expects a Test as its argument. So, that is what is wrong. The right way to fix it is not as obvious, but Ivan already covered that. -Brent