Sha256: 9cfec15e786bc6127ee0369f94b3f420624bc6852455b448ad0d2e1de470fc29
Contents?: true
Size: 786 Bytes
Versions: 277
Compression:
Stored size: 786 Bytes
Contents
{-# LANGUAGE OverloadedStrings #-}
module WordProblem (answer) where
import Data.Text (pack)
import Data.List (foldl')
import Control.Applicative ((<|>))
import Data.Attoparsec.Text
( Parser, signed, decimal, space, maybeResult, parse, many' )
answerParser :: Parser Int
answerParser = do
n <- "What is " *> signed decimal
ops <- many' (space *> operation)
"?" *> pure (foldl' (flip ($)) n ops)
answer :: String -> Maybe Int
answer = maybeResult . parse answerParser . pack
operation :: Parser (Int -> Int)
operation = (flip <$> operator) <* space <*> signed decimal
operator :: Parser (Int -> Int -> Int)
operator = "plus" *> pure (+) <|>
"minus" *> pure (-) <|>
"multiplied by" *> pure (*) <|>
"divided by" *> pure div
Version data entries
277 entries across 277 versions & 1 rubygems