Safe Haskell	None
Language	Haskell2010

Hedgehog.Internal.Source

Contents

Re-exports from GHC.Stack

Synopsis

newtype LineNo = LineNo {
- unLineNo :: Int
}
newtype ColumnNo = ColumnNo {
- unColumnNo :: Int
}
data Span = Span {
- spanFile :: ! FilePath
- spanStartLine :: ! LineNo
- spanStartColumn :: ! ColumnNo
- spanEndLine :: ! LineNo
- spanEndColumn :: ! ColumnNo
}
getCaller :: CallStack -> Maybe Span
data CallStack
type HasCallStack = ?callStack :: CallStack
callStack :: HasCallStack => CallStack
withFrozenCallStack :: HasCallStack => ( HasCallStack => a) -> a

Documentation

newtype LineNo Source #

Constructors

LineNo
Fields unLineNo :: Int

Instances

Instances details

Enum LineNo Source #
Instance details Defined in Hedgehog.Internal.Source Methods succ :: LineNo -> LineNo Source # pred :: LineNo -> LineNo Source # toEnum :: Int -> LineNo Source # fromEnum :: LineNo -> Int Source # enumFrom :: LineNo -> [ LineNo ] Source # enumFromThen :: LineNo -> LineNo -> [ LineNo ] Source # enumFromTo :: LineNo -> LineNo -> [ LineNo ] Source # enumFromThenTo :: LineNo -> LineNo -> LineNo -> [ LineNo ] Source #
Eq LineNo Source #
Instance details Defined in Hedgehog.Internal.Source Methods (==) :: LineNo -> LineNo -> Bool Source # (/=) :: LineNo -> LineNo -> Bool Source #
Integral LineNo Source #
Instance details Defined in Hedgehog.Internal.Source Methods quot :: LineNo -> LineNo -> LineNo Source # rem :: LineNo -> LineNo -> LineNo Source # div :: LineNo -> LineNo -> LineNo Source # mod :: LineNo -> LineNo -> LineNo Source # quotRem :: LineNo -> LineNo -> ( LineNo , LineNo ) Source # divMod :: LineNo -> LineNo -> ( LineNo , LineNo ) Source # toInteger :: LineNo -> Integer Source #
Num LineNo Source #
Instance details Defined in Hedgehog.Internal.Source Methods (+) :: LineNo -> LineNo -> LineNo Source # (-) :: LineNo -> LineNo -> LineNo Source # (*) :: LineNo -> LineNo -> LineNo Source # negate :: LineNo -> LineNo Source # abs :: LineNo -> LineNo Source # signum :: LineNo -> LineNo Source # fromInteger :: Integer -> LineNo Source #
Ord LineNo Source #
Instance details Defined in Hedgehog.Internal.Source Methods compare :: LineNo -> LineNo -> Ordering Source # (<) :: LineNo -> LineNo -> Bool Source # (<=) :: LineNo -> LineNo -> Bool Source # (>) :: LineNo -> LineNo -> Bool Source # (>=) :: LineNo -> LineNo -> Bool Source # max :: LineNo -> LineNo -> LineNo Source # min :: LineNo -> LineNo -> LineNo Source #
Real LineNo Source #
Instance details Defined in Hedgehog.Internal.Source Methods toRational :: LineNo -> Rational Source #
Show LineNo Source #
Instance details Defined in Hedgehog.Internal.Source Methods showsPrec :: Int -> LineNo -> ShowS Source # show :: LineNo -> String Source # showList :: [ LineNo ] -> ShowS Source #

newtype ColumnNo Source #

Constructors

ColumnNo
Fields unColumnNo :: Int

Instances

Instances details

Enum ColumnNo Source #
Instance details Defined in Hedgehog.Internal.Source Methods succ :: ColumnNo -> ColumnNo Source # pred :: ColumnNo -> ColumnNo Source # toEnum :: Int -> ColumnNo Source # fromEnum :: ColumnNo -> Int Source # enumFrom :: ColumnNo -> [ ColumnNo ] Source # enumFromThen :: ColumnNo -> ColumnNo -> [ ColumnNo ] Source # enumFromTo :: ColumnNo -> ColumnNo -> [ ColumnNo ] Source # enumFromThenTo :: ColumnNo -> ColumnNo -> ColumnNo -> [ ColumnNo ] Source #
Eq ColumnNo Source #
Instance details Defined in Hedgehog.Internal.Source Methods (==) :: ColumnNo -> ColumnNo -> Bool Source # (/=) :: ColumnNo -> ColumnNo -> Bool Source #
Integral ColumnNo Source #
Instance details Defined in Hedgehog.Internal.Source Methods quot :: ColumnNo -> ColumnNo -> ColumnNo Source # rem :: ColumnNo -> ColumnNo -> ColumnNo Source # div :: ColumnNo -> ColumnNo -> ColumnNo Source # mod :: ColumnNo -> ColumnNo -> ColumnNo Source # quotRem :: ColumnNo -> ColumnNo -> ( ColumnNo , ColumnNo ) Source # divMod :: ColumnNo -> ColumnNo -> ( ColumnNo , ColumnNo ) Source # toInteger :: ColumnNo -> Integer Source #
Num ColumnNo Source #
Instance details Defined in Hedgehog.Internal.Source Methods (+) :: ColumnNo -> ColumnNo -> ColumnNo Source # (-) :: ColumnNo -> ColumnNo -> ColumnNo Source # (*) :: ColumnNo -> ColumnNo -> ColumnNo Source # negate :: ColumnNo -> ColumnNo Source # abs :: ColumnNo -> ColumnNo Source # signum :: ColumnNo -> ColumnNo Source # fromInteger :: Integer -> ColumnNo Source #
Ord ColumnNo Source #
Instance details Defined in Hedgehog.Internal.Source Methods compare :: ColumnNo -> ColumnNo -> Ordering Source # (<) :: ColumnNo -> ColumnNo -> Bool Source # (<=) :: ColumnNo -> ColumnNo -> Bool Source # (>) :: ColumnNo -> ColumnNo -> Bool Source # (>=) :: ColumnNo -> ColumnNo -> Bool Source # max :: ColumnNo -> ColumnNo -> ColumnNo Source # min :: ColumnNo -> ColumnNo -> ColumnNo Source #
Real ColumnNo Source #
Instance details Defined in Hedgehog.Internal.Source Methods toRational :: ColumnNo -> Rational Source #
Show ColumnNo Source #
Instance details Defined in Hedgehog.Internal.Source Methods showsPrec :: Int -> ColumnNo -> ShowS Source # show :: ColumnNo -> String Source # showList :: [ ColumnNo ] -> ShowS Source #

data Span Source #

Constructors

Span
Fields spanFile :: ! FilePath spanStartLine :: ! LineNo spanStartColumn :: ! ColumnNo spanEndLine :: ! LineNo spanEndColumn :: ! ColumnNo

Instances

Instances details

Eq Span Source #
Instance details Defined in Hedgehog.Internal.Source Methods (==) :: Span -> Span -> Bool Source # (/=) :: Span -> Span -> Bool Source #
Ord Span Source #
Instance details Defined in Hedgehog.Internal.Source Methods compare :: Span -> Span -> Ordering Source # (<) :: Span -> Span -> Bool Source # (<=) :: Span -> Span -> Bool Source # (>) :: Span -> Span -> Bool Source # (>=) :: Span -> Span -> Bool Source # max :: Span -> Span -> Span Source # min :: Span -> Span -> Span Source #
Show Span Source #
Instance details Defined in Hedgehog.Internal.Source Methods showsPrec :: Int -> Span -> ShowS Source # show :: Span -> String Source # showList :: [ Span ] -> ShowS Source #

getCaller :: CallStack -> Maybe Span Source #

Re-exports from GHC.Stack

data CallStack Source #

CallStack s 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>:2:1 in interactive:Ghci1

GHC solves HasCallStack constraints in three steps:

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 .
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).
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.

CallStack s 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.

Since: base-4.8.1.0

Instances

Instances details

IsList CallStack	Be aware that 'fromList . toList = id' only for unfrozen `CallStack` s, since `toList` removes frozenness information. Since: base-4.9.0.0
Instance details Defined in GHC.Exts Associated Types type Item CallStack Source # Methods fromList :: [ Item CallStack ] -> CallStack Source # fromListN :: Int -> [ Item CallStack ] -> CallStack Source # toList :: CallStack -> [ Item CallStack ] Source #
Show CallStack	Since: base-4.9.0.0
Instance details Defined in GHC.Show Methods showsPrec :: Int -> CallStack -> ShowS Source # show :: CallStack -> String Source # showList :: [ CallStack ] -> ShowS Source #
NFData CallStack	Since: deepseq-1.4.2.0
Instance details Defined in Control.DeepSeq Methods rnf :: CallStack -> () Source #
type Item CallStack
Instance details Defined in GHC.Exts type Item CallStack = ( String , SrcLoc )

type HasCallStack = ?callStack :: CallStack Source #

Request a CallStack.

NOTE: The implicit parameter ?callStack :: CallStack is an implementation detail and should not be considered part of the CallStack API, we may decide to change the implementation in the future.

Since: base-4.9.0.0

callStack :: HasCallStack => CallStack Source #

Return the current CallStack .

Does *not* include the call-site of callStack .

Since: base-4.9.0.0

withFrozenCallStack :: HasCallStack => ( HasCallStack => a) -> a Source #

Perform some computation without adding new entries to the CallStack .

Since: base-4.9.0.0