ghc-7.4.1: The GHC API

Safe Haskell	Safe-Infered

Literal

Contents

Main data type

Synopsis

Main data type

data Literal Source

So-called Literals are one of:

An unboxed (machine) literal (MachInt, MachFloat, etc.), which is presumed to be surrounded by appropriate constructors (Int#, etc.), so that the overall thing makes sense.
The literal derived from the label mentioned in a "foreign label" declaration (MachLabel)

Constructors

MachChar Char	`Char#` - at least 31 bits. Create with `mkMachChar`
MachStr FastString	A string-literal: stored and emitted UTF-8 encoded, we'll arrange to decode it at runtime. Also emitted with a `'\0'` terminator. Create with `mkMachString`
MachNullAddr	The `NULL` pointer, the only pointer value that can be represented as a Literal. Create with `nullAddrLit`
MachInt Integer	`Int#` - at least `WORD_SIZE_IN_BITS` bits. Create with `mkMachInt`
MachInt64 Integer	`Int64#` - at least 64 bits. Create with `mkMachInt64`
MachWord Integer	`Word#` - at least `WORD_SIZE_IN_BITS` bits. Create with `mkMachWord`
MachWord64 Integer	`Word64#` - at least 64 bits. Create with `mkMachWord64`
MachFloat Rational	`Float#`. Create with `mkMachFloat`
MachDouble Rational	`Double#`. Create with `mkMachDouble`
MachLabel FastString (Maybe Int) FunctionOrData	A label literal. Parameters: 1) The name of the symbol mentioned in the declaration 2) The size (in bytes) of the arguments the label expects. Only applicable with `stdcall` labels. `Just x` => `<x>` will be appended to label name when emitting assembly.
LitInteger Integer Id

Instances

Eq Literal
Data Literal
Ord Literal
Show Literal
Typeable Literal
Outputable Literal
Binary Literal

Creating Literals

mkMachInt :: Integer -> Literal Source

Creates a Literal of type Int#

mkMachWord :: Integer -> Literal Source

Creates a Literal of type Word#

mkMachInt64 :: Integer -> Literal Source

Creates a Literal of type Int64#

mkMachWord64 :: Integer -> Literal Source

Creates a Literal of type Word64#

mkMachFloat :: Rational -> Literal Source

Creates a Literal of type Float#

mkMachDouble :: Rational -> Literal Source

Creates a Literal of type Double#

mkMachChar :: Char -> Literal Source

Creates a Literal of type Char#

mkMachString :: String -> Literal Source

Creates a Literal of type Addr#, which is appropriate for passing to e.g. some of the "error" functions in GHC.Err such as GHC.Err.runtimeError

mkLitInteger :: Integer -> Id -> Literal Source

Operations on Literals

literalType :: Literal -> Type Source

Find the Haskell Type the literal occupies

hashLiteral :: Literal -> Int Source

absentLiteralOf :: TyCon -> Maybe Literal Source

pprLiteral :: (SDoc -> SDoc) -> Literal -> SDoc Source

Predicates on Literals and their contents

litIsDupable :: Literal -> Bool Source

True if code space does not go bad if we duplicate this literal Currently we treat it just like litIsTrivial

litIsTrivial :: Literal -> Bool Source

True if there is absolutely no penalty to duplicating the literal. False principally of strings

litIsLifted :: Literal -> Bool Source

inIntRange, inWordRange :: Integer -> Bool Source

tARGET_MAX_INT :: Integer Source

inCharRange :: Char -> Bool Source

isZeroLit :: Literal -> Bool Source

Tests whether the literal represents a zero of whatever type it is

litFitsInChar :: Literal -> Bool Source

Coercions

word2IntLit, double2FloatLit, float2DoubleLit, int2DoubleLit, double2IntLit, int2FloatLit, float2IntLit, int2CharLit, char2IntLit, narrow32WordLit, narrow16WordLit, narrow8WordLit, narrow32IntLit, narrow16IntLit, narrow8IntLit, int2WordLit :: Literal -> Literal Source

nullAddrLit :: Literal Source