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    1 -- -----------------------------------------------------------------------------
    2 --
    3 -- (c) The University of Glasgow, 2005-2007
    4 --
    5 -- Running statements interactively
    6 --
    7 -- -----------------------------------------------------------------------------
    8 
    9 module GHC.Runtime.Eval.Types (
   10         Resume(..), ResumeBindings, IcGlobalRdrEnv(..),
   11         History(..), ExecResult(..),
   12         SingleStep(..), isStep, ExecOptions(..)
   13         ) where
   14 
   15 import GHC.Prelude
   16 
   17 import GHCi.RemoteTypes
   18 import GHCi.Message (EvalExpr, ResumeContext)
   19 import GHC.Types.Id
   20 import GHC.Types.Name
   21 import GHC.Types.TyThing
   22 import GHC.Types.BreakInfo
   23 import GHC.Types.Name.Reader
   24 import GHC.Types.SrcLoc
   25 import GHC.Utils.Exception
   26 
   27 import Data.Word
   28 import GHC.Stack.CCS
   29 
   30 data ExecOptions
   31  = ExecOptions
   32      { execSingleStep :: SingleStep         -- ^ stepping mode
   33      , execSourceFile :: String             -- ^ filename (for errors)
   34      , execLineNumber :: Int                -- ^ line number (for errors)
   35      , execWrap :: ForeignHValue -> EvalExpr ForeignHValue
   36      }
   37 
   38 data SingleStep
   39    = RunToCompletion
   40    | SingleStep
   41    | RunAndLogSteps
   42 
   43 isStep :: SingleStep -> Bool
   44 isStep RunToCompletion = False
   45 isStep _ = True
   46 
   47 data ExecResult
   48   = ExecComplete
   49        { execResult :: Either SomeException [Name]
   50        , execAllocation :: Word64
   51        }
   52   | ExecBreak
   53        { breakNames :: [Name]
   54        , breakInfo :: Maybe BreakInfo
   55        }
   56 
   57 -- | Essentially a GlobalRdrEnv, but with additional cached values to allow
   58 -- efficient re-calculation when the imports change.
   59 -- Fields are strict to avoid space leaks (see T4029)
   60 -- All operations are in GHC.Runtime.Context.
   61 -- See Note [icReaderEnv recalculation]
   62 data IcGlobalRdrEnv = IcGlobalRdrEnv
   63   { igre_env :: !GlobalRdrEnv
   64     -- ^ The final environment
   65   , igre_prompt_env :: !GlobalRdrEnv
   66     -- ^ Just the things defined at the prompt (excluding imports!)
   67   }
   68 
   69 data Resume = Resume
   70        { resumeStmt      :: String       -- the original statement
   71        , resumeContext   :: ForeignRef (ResumeContext [HValueRef])
   72        , resumeBindings  :: ResumeBindings
   73        , resumeFinalIds  :: [Id]         -- [Id] to bind on completion
   74        , resumeApStack   :: ForeignHValue -- The object from which we can get
   75                                         -- value of the free variables.
   76        , resumeBreakInfo :: Maybe BreakInfo
   77                                         -- the breakpoint we stopped at
   78                                         -- (module, index)
   79                                         -- (Nothing <=> exception)
   80        , resumeSpan      :: SrcSpan      -- just a copy of the SrcSpan
   81                                         -- from the ModBreaks,
   82                                         -- otherwise it's a pain to
   83                                         -- fetch the ModDetails &
   84                                         -- ModBreaks to get this.
   85        , resumeDecl      :: String       -- ditto
   86        , resumeCCS       :: RemotePtr CostCentreStack
   87        , resumeHistory   :: [History]
   88        , resumeHistoryIx :: Int           -- 0 <==> at the top of the history
   89        }
   90 
   91 type ResumeBindings = ([TyThing], IcGlobalRdrEnv)
   92 
   93 data History
   94    = History {
   95         historyApStack   :: ForeignHValue,
   96         historyBreakInfo :: BreakInfo,
   97         historyEnclosingDecls :: [String]  -- declarations enclosing the breakpoint
   98    }