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Within LTS Haskell 24.50 (ghc-9.10.3)

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1. traceShow :: Show a => a -> b -> b

   base	Debug.Trace

   Like trace, but uses show on the argument to convert it to a String. This makes it convenient for printing the values of interesting variables or expressions inside a function. For example, here we print the values of the variables x and y:

   >>> let f x y = traceShow ("x", x, "y", y) (x + y) in f (1+2) 5
   ("x",3,"y",5)
   8
   

   Note in this example we also create simple labels just by including some strings.

2. traceShowId :: Show a => a -> a

   base	Debug.Trace

   Like traceShow but returns the shown value instead of a third value.

   >>> traceShowId (1+2+3, "hello" ++ "world")
   (6,"helloworld")
   (6,"helloworld")
   

3. traceShowM :: (Show a, Applicative f) => a -> f ()

   base	Debug.Trace

   Like traceM, but uses show on the argument to convert it to a String.

   >>> :{
   do
   x <- Just 3
   traceShowM x
   y <- pure 12
   traceShowM y
   pure (x*2 + y)
   :}
   3
   12
   Just 18
   

4. traceShowWith :: Show b => (a -> b) -> a -> a

   base	Debug.Trace

   Like traceWith, but uses show on the result of the function to convert it to a String.

   >>> traceShowWith length [1,2,3]
   3
   [1,2,3]
   

5. hShow :: Handle -> IO String

   base	System.IO

   hShow is in the IO monad, and gives more comprehensive output than the (pure) instance of Show for Handle.

6. hShow :: Handle -> IO String

   base	GHC.IO.Handle

   hShow is in the IO monad, and gives more comprehensive output than the (pure) instance of Show for Handle.

7. coarbitraryShow :: Show a => a -> Gen b -> Gen b

   QuickCheck	Test.QuickCheck

   coarbitrary helper for lazy people :-).

8. forAllShow :: Testable prop => Gen a -> (a -> String) -> (a -> prop) -> Property

   QuickCheck	Test.QuickCheck

   Like forAll, but with an explicitly given show function.

9. forAllShrinkShow :: Testable prop => Gen a -> (a -> [a]) -> (a -> String) -> (a -> prop) -> Property

   QuickCheck	Test.QuickCheck

   Like forAllShrink, but with an explicitly given show function.

10. functionShow :: (Show a, Read a) => (a -> c) -> a :-> c

    QuickCheck	Test.QuickCheck

    Provides a Function instance for types with Show and Read.

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