implementation module sem

import qualified Data.Map as Map

from Data.Func import $
from StdFunc import o

import Data.Either

import StdString
import StdList
import StdEnum
import RWST
import GenEq

from Text import class Text(concat), instance Text String

import AST

:: Gamma :== 'Map'.Map String Type
:: Constraint :== String
:: Infer a :== RWST [String] [Constraint] Gamma (Either SemError) a
:: SemError
	= ParseError Pos String 
	| UnifyError Pos Type Type 
    | FieldSelectorError Pos Type FieldSelector 
	| OperatorError Pos Op2 Type
    | UndeclaredVariableError Pos String
    | ArgumentMisMatchError Pos String
	| Error String

variableStream :: [String]
variableStream = map toString [1..]

sem :: AST -> SemOutput
sem (AST vd fd) = Right $ (AST vd fd, 'Map'.newMap)

instance toString Gamma where
	toString mp = concat [concat [k, ": ", toString v, "\n"]\\(k, v)<-'Map'.toList mp]

instance toString SemError where
	toString se = "SemError: "