Prelude.hs

-- | Re-exports of base functionality. Note that this module is just
-- used inside the compiler. It's not compiled to JavaScript.
-- Based on the base-extended package (c) 2013 Simon Meier, licensed as BSD3.
{-# LANGUAGE NoImplicitPrelude #-}
module Fay.Compiler.Prelude
  ( module Prelude.Compat -- Partial

  -- * Control modules
  , module Control.Applicative
  , module Control.Arrow -- Partial
  , module Control.Monad.Compat

  -- * Data modules
  , module Data.Char -- Partial
  , module Data.Data -- Partial
  , module Data.Either
  , module Data.Function
  , module Data.List.Compat -- Partial
  , module Data.Maybe
  , module Data.Monoid -- Partial
  , module Data.Ord
  , module Data.Traversable

  -- * Safe
  , module Safe

  -- * Additions
  , anyM
  , io
  , readAllFromProcess
  ) where

import           Control.Applicative
import           Control.Arrow        (first, second, (&&&), (***), (+++), (|||))
import           Control.Monad.Compat hiding (guard)
import           Data.Char            hiding (GeneralCategory (..))
import           Data.Data            (Data (..), Typeable)
import           Data.Either
import           Data.Function        (on)
import           Data.List.Compat
import           Data.Maybe
import           Data.Monoid          (Monoid (..))
import           Data.Ord
import           Data.Traversable
import           Prelude.Compat       hiding (exp, mod)
import           Safe

import           Control.Monad.Except hiding (filterM)
import           System.Exit
import           System.Process

-- | Alias of liftIO, I hate typing it. Hate reading it.
io :: MonadIO m => IO a -> m a
io = liftIO

-- | Do any of the (monadic) predicates match?
anyM :: (Functor m, Applicative m, Monad m) => (a -> m Bool) -> [a] -> m Bool
anyM p l = not . null <$> filterM p l

-- | Read from a process returning both std err and out.
readAllFromProcess :: FilePath -> [String] -> String -> IO (Either (String,String) (String,String))
readAllFromProcess program flags input = do
  (code,out,err) <- readProcessWithExitCode program flags input
  return $ case code of
    ExitFailure 127 -> Left ("cannot find executable " ++ program, "")
    ExitFailure _   -> Left (err, out)
    ExitSuccess     -> Right (err, out)