Language.GroteTrap.Language

The Language type that is the core of GroteTrap.

Language

data Language a

Language connects the syntax of identifiers, numbers, operators and functions with their semantics. GroteTrap is able to derive a parser and evaluator from a Language, as well as convert between source text selections and tree selections.

Constructors

Language

Fields

variable :: String -> a

number :: Int -> a

operators :: [Operator a]

functions :: [Function a]

Operators

data Operator a

Representation of an operator.

Constructors

Unary

An operator expecting one operand.

Fields

opSem1 :: a -> a

opFixity1 :: Fixity1

opPrio :: Int

opToken :: String

Binary

An operator expecting two operands.

Fields

opSem2 :: a -> a -> a

opFixity2 :: Fixity2

opPrio :: Int

opToken :: String

Nary

An infix associative operator that chains together an arbitrary number of operands.

Fields

opSemN :: [a] -> a

opSubranges :: Bool

opPrio :: Int

opToken :: String

data Fixity1

Fixity for unary operators.

Constructors

Prefix

The operator is written before its operand.

Postfix

The operator is written after its operand.

Instances

Enum Fixity1

Eq Fixity1

Show Fixity1

data Fixity2

Fixity for infix binary operators.

Constructors

InfixL

The operator associates to the left.

InfixR

The operator associates to the right.

Instances

Enum Fixity2

Eq Fixity2

Show Fixity2

isUnary :: Operator a -> Bool

isBinary :: Operator a -> Bool

isNary :: Operator a -> Bool

findOperator :: Monad m => String -> [Operator a] -> m (Operator a)

Yields the specified operator in a monad. Fails when there are no operators with the name, or where there are several operators with the name.

Functions

data Function a

Representation of a function.

Constructors

Function

Fields

fnSem :: [a] -> a

fnName :: String

fnArity :: Int

findFunction :: Monad m => String -> [Function a] -> m (Function a)

Yields the function with the specified name. If there are no functions with the name, or if there are several functions with the name, failure is returned.

function1 :: (a -> a) -> String -> Function a

Lifts a unary function to a Function.

function2 :: (a -> a -> a) -> String -> Function a

Lifts a binary function to a Function.