Sha256: fff684e8107fb458324354d478469bb97b6450bdd0f5e19b4e9dd06c9f8d5e12
Contents?: true
Size: 786 Bytes
Versions: 119
Compression:
Stored size: 786 Bytes
Contents
{-# LANGUAGE OverloadedStrings #-}
module WordProblem (answer) where
import Data.Functor (($>))
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)
"?" $> foldl' (flip ($)) 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" $> (+) <|>
"minus" $> (-) <|>
"multiplied by" $> (*) <|>
"divided by" $> div
Version data entries
119 entries across 119 versions & 1 rubygems