Env.OpPrec

In order to parse infix expressions correctly, the compiler must know the precedence and fixity of each operator. Operator precedences are associated with entities and will be checked after renaming was applied. Nevertheless, we need to save precedences for ambiguous names in order to handle them correctly while computing the exported interface of a module.

If no fixity is assigned to an operator, it will be given the default precedence 9 and assumed to be a left-associative operator.

Note: this modified version uses Haskell type Integer for representing the precedence. This change had to be done due to the introduction of unlimited integer constants in the parser / lexer.

Documentation

data OpPrec

Operator precedence.

Constructors

OpPrec Infix Precedence

Instances

Eq OpPrec

Defined in Env.OpPrec

Methods

(==) :: OpPrec -> OpPrec -> Bool

(/=) :: OpPrec -> OpPrec -> Bool

Show OpPrec

Defined in Env.OpPrec

Methods

showsPrec :: Int -> OpPrec -> ShowS

show :: OpPrec -> String

showList :: [OpPrec] -> ShowS

Pretty OpPrec

Defined in Env.OpPrec

Methods

pPrint :: OpPrec -> Doc

pPrintPrec :: Int -> OpPrec -> Doc

pPrintList :: [OpPrec] -> Doc

defaultP :: OpPrec

Default operator declaration (associativity and precedence).

defaultAssoc :: Infix

Default operator associativity.

defaultPrecedence :: Precedence

Default operator precedence.

mkPrec :: Maybe Precedence -> Precedence

type OpPrecEnv = TopEnv PrecInfo

Environment mapping identifiers to their operator precedence.

data PrecInfo

Precedence information for an identifier.

Constructors

PrecInfo QualIdent OpPrec

Instances

Eq PrecInfo

Defined in Env.OpPrec

Methods

(==) :: PrecInfo -> PrecInfo -> Bool

(/=) :: PrecInfo -> PrecInfo -> Bool

Show PrecInfo

Defined in Env.OpPrec

Methods

showsPrec :: Int -> PrecInfo -> ShowS

show :: PrecInfo -> String

showList :: [PrecInfo] -> ShowS

Pretty PrecInfo

Defined in Env.OpPrec

Methods

pPrint :: PrecInfo -> Doc

pPrintPrec :: Int -> PrecInfo -> Doc

pPrintList :: [PrecInfo] -> Doc

Entity PrecInfo

Defined in Env.OpPrec

Methods

origName :: PrecInfo -> QualIdent

merge :: PrecInfo -> PrecInfo -> Maybe PrecInfo

bindP :: ModuleIdent -> Ident -> OpPrec -> OpPrecEnv -> OpPrecEnv

Bind an operator precedence.

lookupP :: Ident -> OpPrecEnv -> [PrecInfo]

Lookup the operator precedence for an Ident.

qualLookupP :: QualIdent -> OpPrecEnv -> [PrecInfo]

Lookup the operator precedence for an QualIdent.

initOpPrecEnv :: OpPrecEnv

Initial OpPrecEnv.