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1. prettyCallStack :: CallStack -> String

   effectful-core	Effectful.Labeled.Error

   Pretty print a CallStack.

2. data CallStack

   effectful-core	Effectful.NonDet

   CallStacks are a lightweight method of obtaining a partial call-stack at any point in the program. A function can request its call-site with the HasCallStack constraint. For example, we can define

   putStrLnWithCallStack :: HasCallStack => String -> IO ()
   

   as a variant of putStrLn that will get its call-site and print it, along with the string given as argument. We can access the call-stack inside putStrLnWithCallStack with callStack.

   >>> :{
   putStrLnWithCallStack :: HasCallStack => String -> IO ()
   putStrLnWithCallStack msg = do
   putStrLn msg
   putStrLn (prettyCallStack callStack)
   :}
   

   Thus, if we call putStrLnWithCallStack we will get a formatted call-stack alongside our string.

   >>> putStrLnWithCallStack "hello"
   hello
   CallStack (from HasCallStack):
   putStrLnWithCallStack, called at <interactive>:... in interactive:Ghci...
   

   GHC solves HasCallStack constraints in three steps:
   1. If there is a CallStack in scope -- i.e. the enclosing function has a HasCallStack constraint -- GHC will append the new call-site to the existing CallStack.
   2. If there is no CallStack in scope -- e.g. in the GHCi session above -- and the enclosing definition does not have an explicit type signature, GHC will infer a HasCallStack constraint for the enclosing definition (subject to the monomorphism restriction).
   3. If there is no CallStack in scope and the enclosing definition has an explicit type signature, GHC will solve the HasCallStack constraint for the singleton CallStack containing just the current call-site.
   CallStacks do not interact with the RTS and do not require compilation with -prof. On the other hand, as they are built up explicitly via the HasCallStack constraints, they will generally not contain as much information as the simulated call-stacks maintained by the RTS. A CallStack is a [(String, SrcLoc)]. The String is the name of function that was called, the SrcLoc is the call-site. The list is ordered with the most recently called function at the head. NOTE: The intrepid user may notice that HasCallStack is just an alias for an implicit parameter ?callStack :: CallStack. This is an implementation detail and should not be considered part of the CallStack API, we may decide to change the implementation in the future.

3. getCallStack :: CallStack -> [([Char], SrcLoc)]

   effectful-core	Effectful.NonDet

   Extract a list of call-sites from the CallStack. The list is ordered by most recent call.

4. prettyCallStack :: CallStack -> String

   effectful-core	Effectful.NonDet

   Pretty print a CallStack.

5. compareLexicographically :: Expr -> Expr -> Ordering

   express	Data.Express

   O(n). Lexicographical structural comparison of Exprs where variables < constants < applications then types are compared before string representations.

   > compareLexicographically one (one -+- one)
   LT
   > compareLexicographically one zero
   GT
   > compareLexicographically (xx -+- zero) (zero -+- xx)
   LT
   > compareLexicographically (zero -+- xx) (zero -+- xx)
   EQ
   

   (cf. compareTy) This comparison is a total order.

6. compareLexicographically :: Expr -> Expr -> Ordering

   express	Data.Express.Core

   O(n). Lexicographical structural comparison of Exprs where variables < constants < applications then types are compared before string representations.

   > compareLexicographically one (one -+- one)
   LT
   > compareLexicographically one zero
   GT
   > compareLexicographically (xx -+- zero) (zero -+- xx)
   LT
   > compareLexicographically (zero -+- xx) (zero -+- xx)
   EQ
   

   (cf. compareTy) This comparison is a total order.

7. reallyDeriveCascading :: Name -> (Name -> DecsQ) -> Name -> DecsQ

   express	Data.Express.Utils.TH

   No documentation available.

8. forAll :: (Show a, IsProperty prop) => Gen a -> (a -> prop) -> Property

   foundation	Foundation.Check

   Running a generator for a specific type under a property

9. finally :: MonadBracket m => m a -> m b -> m a

   foundation	Foundation.Exception

   No documentation available.

10. skipAll :: (ParserSource input, Collection (Chunk input)) => Parser input ()

    foundation	Foundation.Parser

    consume every chunk of the stream

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