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module Main where
import GSyntax
import GF.Embed.EmbedAPI
main :: IO ()
main = do
gr <- file2grammar "math.gfcm"
loop gr
loop :: MultiGrammar -> IO ()
loop gr = do
s <- getLine
interpret gr s
loop gr
interpret :: MultiGrammar -> String -> IO ()
interpret gr s = do
let tss = parseAll gr "Prop" s
case (concat tss) of
[] -> putStrLn "no parse"
t:_ -> print $ answer $ fg t
answer :: GProp -> Bool
answer p = case p of
(GOdd x1) -> odd (value x1)
(GEven x1) -> even (value x1)
(GAnd x1 x2) -> answer x1 && answer x2
value :: GElem -> Int
value e = case e of
GZero -> 0
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