-- Hoogle documentation, generated by Haddock
-- See Hoogle, http://www.haskell.org/hoogle/


-- | Quasiquoters for external commands
--   
--   Features:
--   
--   <ul>
--   <li>Quasiquotation syntax for external commands:</li>
--   </ul>
--   
--   <pre>
--   [sh| echo hello world! |]
--   </pre>
--   
--   <ul>
--   <li>Easy way to define custom quasiquoters (see
--   <tt>examples/CustomQQ.hs</tt>)</li>
--   </ul>
--   
--   <pre>
--   ghci = QQ.quoter $ QQ.callCommand "ghc" ["-ignore-dot-ghci", "-e"]
--   </pre>
--   
--   <ul>
--   <li>Can embed Haskell variables in scripts</li>
--   </ul>
--   
--   <pre>
--   class Embed a where
--     embed :: a -&gt; String
--   
--   instance Embed String
--     embed = id
--   
--   main :: IO ()
--   main = let excl = replicate 3 '!' in -- I'd love to show an example but haddock markup fails here
--   </pre>
--   
--   <ul>
--   <li>Can embed quasiquoters in DSLs (see
--   <tt>examples/CommandT.hs</tt>)</li>
--   </ul>
--   
--   <pre>
--   class Eval r where
--     eval :: String -&gt; [String] -&gt; r
--   
--   instance Eval (IO ExitCode) where
--     eval command args = System.Process.rawSystem command args
--   </pre>
@package command-qq
@version 0.1.0.0


-- | Quasiquoters for external commands
module System.Command.QQ

-- | Quasiquoter for the default shell
--   
--   "default" here means it uses value of <tt>SHELL</tt> environment
--   variable or <tt>/bin/sh</tt> if it is not set.
--   
--   <pre>
--   &gt;&gt;&gt; [sh|echo "hi!"|] :: IO ExitCode
--   hi!
--   ExitSuccess
--   
--   &gt;&gt;&gt; [sh|echo "hi!"|] :: IO String
--   "hi!\n"
--   </pre>
--   
--   Haskell values can be embedded with Ruby-like syntax:
--   
--   <pre>
--   &gt;&gt;&gt; let apples = 7
--   
--   &gt;&gt;&gt; [sh|echo "#{apples} apples!"|] :: IO String
--   "7 apples!\n"
--   </pre>
--   
--   Works only for expressions (obviously):
--   
--   <pre>
--   &gt;&gt;&gt; return 3 :: IO [sh|blah|]
--   
--   &lt;interactive&gt;:116:16:
--       Exception when trying to run compile-time code:
--         this quasiquoter does not support splicing types
--         Code: quoteType sh "blah"
--   </pre>
sh :: QuasiQuoter

-- | Shell commands quasiquoter maker
--   
--   "Shell" here means something that implements the following interface:
--   
--   <pre>
--   &lt;SHELL&gt; -c &lt;COMMAND&gt;
--   </pre>
--   
--   <i>e.g.</i> <tt>sh</tt>, <tt>bash</tt>, <tt>zsh</tt>, <tt>ksh</tt>,
--   <tt>tcsh</tt>, <tt>python</tt>, etc
--   
--   Everything that applies to <a>sh</a> applies to <a>shell</a>
shell :: FilePath -> QuasiQuoter

-- | Interpreter commands quasiquoter maker
--   
--   "Interpreter" here means something that implements the following
--   interface:
--   
--   <pre>
--   &lt;INTERPRETER&gt; -e &lt;COMMAND&gt;
--   </pre>
--   
--   <i>e.g.</i> <tt>perl</tt>, <tt>ruby</tt>, <tt>ghc</tt>, etc
--   
--   Everything that applies to <a>sh</a> applies to <a>interpreter</a>
interpreter :: FilePath -> QuasiQuoter

-- | Construct quasiquoter from function taking the string and producing
--   Haskell expression.
--   
--   Other kinds of quasiquoters (patterns, types or declarations
--   quasiquoters) will fail in compile time
quoter :: (String -> Q Exp) -> QuasiQuoter

-- | Construct Haskell expression for external command call
callCommand :: FilePath -> [String] -> String -> Q Exp

-- | Different interesting return types for quasiquoters
--   
--   Instances here mostly resemble the types of things in
--   <a>System.Process</a>
class Eval r
eval :: Eval r => String -> [String] -> r

-- | Embed haskell values into external commands
--   
--   I recommend using <tt>-XExtendedDefaultRules</tt> for modules where
--   you want to embed values, it would save for annoying type annotations
--   for numeric literals
--   
--   <pre>
--   embed . embed = embed
--   </pre>
class Embed a where embed = show
embed :: Embed a => a -> String
instance Embed String
instance Embed Char
instance Embed Double
instance Embed Float
instance Embed Word64
instance Embed Word32
instance Embed Word16
instance Embed Word8
instance Embed Word
instance Embed Int64
instance Embed Int32
instance Embed Int16
instance Embed Int8
instance Embed Int
instance Embed Integer
instance (i ~ String, o ~ (ExitCode, String, String)) => Eval (i -> IO o)
instance (s ~ ExitCode, o ~ String, e ~ String) => Eval (IO (s, o, e))
instance Eval (IO String)
instance Eval (IO ExitCode)
instance Eval (IO ())