Language.Glambda.Monad

The Glam monad, allowing for pretty-printed output to the user, failing with an error message, and tracking global variables.

The Glam monad

data Glam a

A monad giving Haskeline-like interaction, access to Globals, and the ability to abort with mzero.

Instances

Monad Glam

Functor Glam

Applicative Glam

MonadIO Glam

GlamM Glam

MonadState Globals Glam

runGlam :: Glam () -> InputT IO ()

Run a Glam computation

prompt :: String -> Glam (Maybe String)

Prompt the user for input, returning a string if one is entered. Like getInputLine.

quit :: Glam a

Abort the Glam monad

The GlamE monad

data GlamE a

Like the Glam monad, but also supporting error messages via Docs

Instances

Monad GlamE

Functor GlamE

Applicative GlamE

GlamM GlamE

MonadError Doc GlamE

MonadReader Globals GlamE

runGlamE :: GlamE a -> Glam (Either Doc a)

Run a GlamE computation

issueError :: Doc -> GlamE a

Abort the computation with an error

eitherToGlamE :: Either String a -> GlamE a

Hoist an Either into GlamE

General functions over both glamorous monads

class GlamM m where

Class for the two glamorous monads

Methods

printDoc :: Doc -> m ()

Print a Doc without a newline at the end

printLine :: Doc -> m ()

Print a Doc with a newline

Instances

GlamM GlamE

GlamM Glam