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 :: Monad m => (a -> m Bool) -> [a] -> m Bool
anyM p l = return . 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)