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


-- | shell monad
--   
--   This is a shell monad, for generating shell scripts.
@package shell-monad
@version 0.0.1


-- | A shell script monad
module Control.Monad.Shell

-- | Shell script monad.
data Script a

-- | Generates a shell script, including hashbang, suitable to be written
--   to a file.
script :: Script f -> Text

-- | Generates a single line of shell code.
linearScript :: Script f -> Text

-- | A shell variable.
data Var

-- | Expand a shell variable to its value.
val :: Var -> Q

-- | A shell expression.
data Expr

-- | Indents an Expr
indent :: Expr -> Expr

-- | Adds a shell command to the script.
run :: Text -> [Text] -> Script ()

-- | Variadic argument version of <a>run</a>.
--   
--   The command can be passed any number of arguments. As well as passing
--   Text arguments, it also accepts Var arguments, which passes the value
--   of a shell variable to the command.
--   
--   Convenient usage of <a>cmd</a> requires the following:
--   
--   <pre>
--   {-# LANGUAGE OverloadedStrings, ExtendedDefaultRules #-}
--   {-# OPTIONS_GHC -fno-warn-type-defaults #-}
--   import Control.Monad.Shell
--   import qualified Data.Text.Lazy as T
--   default (L.Text)
--   </pre>
--   
--   This allows writing, for example:
--   
--   <pre>
--   demo = script $ do
--     cmd "echo" "hello, world"
--     name &lt;- newVar "name"
--     readVar name
--     cmd "echo" "hello" name
--   </pre>
cmd :: ShellCmd result => Text -> result

-- | Adds an Expr to the script.
add :: Expr -> Script ()

-- | Adds a comment that is embedded in the generated shell script.
comment :: Text -> Script ()

-- | Defines a new shell variable.
--   
--   The name of the variable that appears in the shell script will be
--   based on provided name, but each call to newVar will generate a new,
--   unique variable name.
newVar :: Text -> Script Var

-- | Creates a new shell variable, with an initial value.
newVarContaining :: Text -> Text -> Script Var

-- | Gets a Var that refers to a global variable, such as PATH
globalVar :: Text -> Script Var

-- | Defines a shell function, and returns an action that can be run to
--   call the function.
--   
--   TODO parameter passing to the function
func :: Script () -> Script (Script ())

-- | Runs the command, and separates its output into parts (using the IFS)
--   
--   The action is run for each part, passed a Var containing the part.
forCmd :: Script () -> (Var -> Script ()) -> Script ()

-- | Quotes the value to allow it to be safely exposed to the shell.
--   
--   The method used is to replace ' with '"'"' and wrap the value inside
--   single quotes. This works for POSIX shells, as well as other shells
--   like csh.
quote :: Text -> Q

-- | Generates shell code to read a variable from stdin.
readVar :: Var -> Script ()

-- | Pipes together two Scripts.
(-|-) :: Script () -> Script () -> Script ()
instance Eq Var
instance Ord Var
instance Show Var
instance Eq Q
instance Ord Q
instance Show Q
instance Eq Func
instance Ord Func
instance Show Func
instance f ~ () => ShellCmd (Script f)
instance (CmdArg arg, ShellCmd result) => ShellCmd (arg -> result)
instance CmdArg Q
instance CmdArg Var
instance CmdArg Text
instance Monoid Env
instance Monad Script
instance Monoid Q