base-4.7.0.0: Basic libraries

Copyright | (c) The University of Glasgow 2011
License | see libraries/base/LICENSE
Maintainer | cvs-ghc@haskell.org
Stability | internal
Portability | non-portable (GHC Extensions)
Safe Haskell | None
Language | Haskell2010

GHC.Stack

Contents

- Call stack
- Internals

Description

Access to GHC's call-stack simulation

Since: 4.5.0.0

Synopsis

- currentCallStack :: IO [String]
- whoCreated :: a -> IO [String]
- errorWithStackTrace :: String -> a
- data CostCentreStack
- data CostCentre
- getCurrentCCS :: dummy -> IO (Ptr CostCentreStack)
- getCCSOf :: a -> IO (Ptr CostCentreStack)
- ccsCC :: Ptr CostCentreStack -> IO (Ptr CostCentre)
- ccsParent :: Ptr CostCentreStack -> IO (Ptr CostCentreStack)
- ccLabel :: Ptr CostCentre -> IO CString
- ccModule :: Ptr CostCentre -> IO CString
- ccSrcSpan :: Ptr CostCentre -> IO CString
- ccsToStrings :: Ptr CostCentreStack -> IO [String]
- renderStack :: [String] -> String

# Call stack

currentCallStack :: IO [String]

returns a '[String]' representing the current call stack. This can be useful for debugging.

The implementation uses the call-stack simulation maintined by the profiler, so it only works if the program was compiled with `-prof` and contains suitable SCC annotations (e.g. by using `-fprof-auto`). Otherwise, the list returned is likely to be empty or uninformative.

Since: 4.5.0.0

whoCreated :: a -> IO [String]

Get the stack trace attached to an object.

Since: 4.5.0.0

errorWithStackTrace :: String -> a

Like the function `error`, but appends a stack trace to the error message if one is available.

Since: 4.7.0.0

# Internals

data CostCentreStack

data CostCentre

getCurrentCCS :: dummy -> IO (Ptr CostCentreStack)

getCCSOf :: a -> IO (Ptr CostCentreStack)

ccsCC :: Ptr CostCentreStack -> IO (Ptr CostCentre)

ccsParent :: Ptr CostCentreStack -> IO (Ptr CostCentreStack)

ccLabel :: Ptr CostCentre -> IO CString

ccModule :: Ptr CostCentre -> IO CString

ccSrcSpan :: Ptr CostCentre -> IO CString

ccsToStrings :: Ptr CostCentreStack -> IO [String]

renderStack :: [String] -> String