Game.Goatee.Lib.Renderer

Common definitions for a renderer that supports failure.

Documentation

type Render = WriterT String (Except String)

A monad for accumulating string output with the possibility of failure.

runRender :: Render a -> Either String String

Returns either the rendered result on the right, or a message describing a failure on the left.

rendererOf :: Show a => String -> (a -> Render ()) -> a -> Render ()

Wraps a renderer in an exception handler that, when the renderer or something it calls fails, will add context about this renderer's invocation to the failure message.