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    1 {-|
    2 Module:      Y2015.Util
    3 Description: Shared functions for Advent of Code Solutions.
    4 License:     MIT
    5 Maintainer:  @tylerjl
    6 
    7 Shared functions that support solutions to problems for  the
    8 <adventofcode.com> challenges.
    9 -}
   10 
   11 module Y2015.Util
   12     ( (<&&>)
   13     , (<||>)
   14     , regularParse
   15     , intParser
   16     , regularParse'
   17     ,intParser') where
   18 
   19 import           Control.Monad       (liftM2)
   20 import qualified Text.Parsec as      P
   21 import           Text.Parsec.Char    (digit)
   22 import           Text.Parsec.String  (Parser)
   23 import qualified Text.Parsec.Text as T
   24 import           Data.Text           (Text)
   25 
   26 -- |Combinator operator for predicates
   27 (<&&>) :: (a -> Bool) -- ^ Predicate 1
   28        -> (a -> Bool) -- ^ Predicate 2
   29        -> a           -- ^ Predicate target
   30        -> Bool        -- ^ Logical and for predicates
   31 (<&&>) = liftM2 (&&)
   32 
   33 -- |Combinator operator for predicates
   34 (<||>) :: (a -> Bool) -- ^ Predicate 1
   35        -> (a -> Bool) -- ^ Predicate 2
   36        -> a           -- ^ Predicate target
   37        -> Bool        -- ^ Logical or for predicates
   38 (<||>) = liftM2 (||)
   39 
   40 -- |Generic parsing wrapper
   41 regularParse :: Parser a -> String -> Either P.ParseError a
   42 regularParse p = P.parse p ""
   43 
   44 -- |Generic parser for `Text` values
   45 regularParse' :: T.Parser a -> Text -> Either P.ParseError a
   46 regularParse' p = P.parse p ""
   47 
   48 -- |Generic 'Int' parser
   49 intParser :: Parser Int -- ^ Parsec parser for 'Int' types
   50 intParser = read <$> P.many1 digit
   51 
   52 -- |Generic 'Int' parser for `Text`
   53 intParser' :: T.Parser Int -- ^ Parsec parser for 'Int' types
   54 intParser' = read <$> P.many1 digit