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-- the Generic Model Parser Abstract Syntax

-- Copyright 2007, Lutz Schroeder and Georgel Calin

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module GMPAS where

import Language.Haskell.Pretty

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-- Abstract Syntax

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type Mindex = String -- index of the Modal Operator

data Otype = Square | Angle -- type of the Modal Operator

data Mop = Mindex Otype -- Modal Operator

data Formula = F -- datatype for the formulae

| T

| Neg Formula -- "~"

| And Formula Formula -- "/\"

| Or Formula Formula -- "\/"

| If Formula Formula -- "->"

| Fi Formula Formula -- "<-"

| Iff Formula Formula -- "<->"

| Mop Formula

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-- Pretty print Abstract Syntax

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instance Show Formula where

-- to be done