glambda-1.0.1: A simply typed lambda calculus interpreter, written with GADTs

Copyright(C) 2015 Richard Eisenberg
LicenseBSD-style (see LICENSE)
MaintainerRichard Eisenberg (eir@cis.upenn.edu)
Stabilityexperimental
Safe HaskellNone
LanguageHaskell2010

Language.Glambda.Token

Contents

Description

Defines a lexical token

Synopsis

Arithmetic operators

data ArithOp ty where Source

An ArithOp ty is an operator on numbers that produces a result of type ty

Constructors

Plus :: ArithOp Int 
Minus :: ArithOp Int 
Times :: ArithOp Int 
Divide :: ArithOp Int 
Mod :: ArithOp Int 
Less :: ArithOp Bool 
LessE :: ArithOp Bool 
Greater :: ArithOp Bool 
GreaterE :: ArithOp Bool 
Equals :: ArithOp Bool 

Instances

Eq (ArithOp ty) 
Show (ArithOp ty) 
Pretty (ArithOp ty) 

data UArithOp where Source

UArithOp ("unchecked ArithOp") is an existential package for an ArithOp

Constructors

UArithOp :: ITy ty => ArithOp ty -> UArithOp 

Instances

eqArithOp :: ArithOp ty1 -> ArithOp ty2 -> Bool Source

Compare two ArithOps (potentially of different types) for equality

Unchecked synonyms for arithmetic operators

uPlus :: UArithOp Source

uMinus :: UArithOp Source

uTimes :: UArithOp Source

uDivide :: UArithOp Source

uMod :: UArithOp Source

uLess :: UArithOp Source

uLessE :: UArithOp Source

uGreater :: UArithOp Source

uGreaterE :: UArithOp Source

uEquals :: UArithOp Source

Tokens

data Token Source

A lexed token

Constructors

LParen 
RParen 
Lambda 
Dot 
Arrow 
Colon 
ArithOp UArithOp 
Int Int 
Bool Bool 
If 
Then 
Else 
FixT 
Assign 
Semi 
Name String 

Instances

data LToken Source

A lexed token with location information attached

Constructors

L SourcePos Token 

Instances

unLoc :: LToken -> Token Source

Remove location information from an LToken

unArithOp :: Token -> Maybe UArithOp Source

Perhaps extract a UArithOp

unInt :: Token -> Maybe Int Source

Perhaps extract an Int

unBool :: Token -> Maybe Bool Source

Perhaps extract an Bool

unName :: Token -> Maybe String Source

Perhaps extract a String