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Text.LaTeX.Base.Writer

Contents

Description

The writer monad applied to LaTeX values. Useful to compose LaTeX values using the do notation:

 anExample :: Monad m => LaTeXT m ()
 anExample = do
   documentclass [] article
   author "Daniel Monad"
   title "LaTeX and do notation"
   document $ do
     maketitle
     section "Some words"
     "Using " ; texttt "do" ; " notation "
     "you avoid many ocurrences of the "
     texttt "(<>)" ; " operator and a lot of "
     "parentheses. With the cost of a monad."

Since LaTeXT is a monad transformer, you can do also:

 anotherExample :: LaTeXT IO ()
 anotherExample = lift (readFileTex "foo") >>= verbatim

This way, it is easy (without carrying arguments) to include IO outputs in the LaTeX document, like files, times or random objects.

Another approach could be to have custom counters, label management or any other user-defined feature.

Of course, you can always use the simpler interface provided by the plain LaTeX type.

Another thing you should know about the LaTeX Writer Monad. Don't try to get values from computations with no results (like raw foo).

Synopsis

`LaTeXT` writer

data LaTeXT m a Source

WriterT monad transformer applied to LaTeX values.

Instances

MonadTrans LaTeXT
Monad m => Monad (LaTeXT m)
Functor f => Functor (LaTeXT f)
Applicative f => Applicative (LaTeXT f)
MonadIO m => MonadIO (LaTeXT m)
Monad m => Eq (LaTeXT m a)	Warning: this instance only exists for the `Num` instance.
Monad m => Floating (LaTeXT m a)	Undefined methods: `asinh`, `atanh` and `acosh`.
Monad m => Fractional (LaTeXT m a)	Division uses the LaTeX `frac` command.
Monad m => Num (LaTeXT m a)	Careful! Method `signum` is undefined. Don't use it!
Monad m => Show (LaTeXT m a)	Warning: this instance only exists for the `Num` instance.
Monad m => IsString (LaTeXT m a)	Be careful when using `fromString` over a `LaTeXT` value, the returned value of the computation is bottom (i.e. `undefined`).
Monad m => Monoid (LaTeXT m a)	`mappend` `=` `>>`.
Monad m => LaTeXC (LaTeXT m a)

type LaTeXT_ m = LaTeXT m ()Source

Type synonym for empty LaTeXT computations.

runLaTeXT :: Monad m => LaTeXT m a -> m (Either String a, LaTeX)Source

Running a LaTeXT computation returns the final LaTeX value and either a String if the computation didn't contain any value or the value itself otherwise.

execLaTeXT :: Monad m => LaTeXT m a -> m LaTeX Source

This is the usual way to run the LaTeXT monad and obtain a LaTeX value.

 execLaTeXT = liftM snd . runLaTeXT

If anExample is defined as above (at the top of this module documentation), use the following to get the LaTeX value generated out.

 myLaTeX :: Monad m => m LaTeX
 myLaTeX = execLaTeXT anExample

execLaTeXTWarn :: Monad m => LaTeXT m a -> m (LaTeX, [Warning])Source

Version of execLaTeXT with possible warning messages. This function applies checkAll to the LaTeX output.

extractLaTeX :: Monad m => LaTeXT m a -> LaTeXT m (a, LaTeX)Source

This function run a LaTeXT computation, lifting the result again in the monad.

extractLaTeX_ :: Monad m => LaTeXT m a -> LaTeXT m LaTeX Source

Executes a LaTeXT computation, embedding it again in the LaTeXT monad.

 extractLaTeX_ = liftM snd . extractLaTeX

This function was heavily used in the past by HaTeX-meta to generate those .Monad modules. The current purpose is to implement the LaTeXC instance of LaTeXT, which is closely related.

textell :: Monad m => LaTeX -> LaTeXT m ()Source

With textell you can append LaTeX values to the state of the LaTeXT monad.

rendertexM :: (Render a, Monad m) => a -> LaTeXT m ()Source

Just like rendertex, but with LaTeXT output.

 rendertexM = textell . rendertex

liftFun :: Monad m => (LaTeX -> LaTeX) -> LaTeXT m a -> LaTeXT m aSource

Lift a function over LaTeX values to a function acting over the state of a LaTeXT computation.

liftOp :: Monad m => (LaTeX -> LaTeX -> LaTeX) -> LaTeXT m a -> LaTeXT m b -> LaTeXT m bSource

Lift an operator over LaTeX values to an operator acting over the state of two LaTeXT computations.

Note: The returned value is the one returned by the second argument of the lifted operator.

Errors

throwError :: Monad m => String -> LaTeXT m aSource

The fail method of the LaTeXT monad.

merror :: Monad m => String -> LaTeXT m a -> LaTeXT m bSource

Function merror casts a value contained in a monad m to the bottom value of another type. If you try to evaluate this value, you will get an error message with the String passed as argument to merror.

Re-export

lift :: MonadTrans t => forall m a. Monad m => m a -> t m a

Lift a computation from the argument monad to the constructed monad.

liftIO :: MonadIO m => forall a. IO a -> m a

Lift a computation from the IO monad.

LaTeXT writer

Errors

Re-export

`LaTeXT` writer