*Task*

How to use pretty-printed documents in LaTeX.

*Description*

The back-end [[AboxToLaTex][abox2latex]] produces LaTeX code according to the formatting defined in a [[BoxLanguage][Box]] term. In order to process this LaTeX code by latex, the `boxenv' style file is required.

The location of this style file depends on your GPP installation but [[AboxToLaTex][abox2latex]] includes a comment section in the generated LaTeX code that tells you where to find the style file.

A generated LaTeX file can be incorporated in a larger LaTeX document as follows:

	1. Determine the location of the boxenv style file by inspecting the comments at the beginning of example.tex.

	2. Add this location to your TEXINPUTS environment variable.

	3. Add `\usepackage{boxenv}' to the preamble of main.tex.

	4. Import the generated LaTeX file using `\input'.
	
	5. Process the file by latex.

The paper [[http://www.cs.uu.nl/groups/ST/twiki/bin/view/Merijn/PaperALaTeXStyleFileForFormattingBOXExpressions][A LaTeX Style File For Formatting BOX Expressions]]
contains detailed information about the boxenv style file and its use.

*Changing Fonts*

You can change how text is displayed by LaTeX by redefining macros in a configuration file 'box-fonts.def'. The following macros can be defined:

	KWf:: Defines how keywords are formatted (default '\textbf{...}')
	VARf:: Defines how variables are formatted (default '\textit{...}')
	NUMf:: Defines how numbers are formatted (default '\textrm{...}')
	MATHf:: Defines how mathematical symbols are formatted (default '\ensuremath{...}')
	COMMF:: Defines how to comments are formatted (default '\textrm{...}') 
	

*Changing Symbols*

You can instruct [[AboxToLaTex][abox2latex]] to map symbols in an abox term to special LaTeX symbols. To that end, you create an abbreviations table containing mappings from [[BoxLanguage][Box]] symbols to LaTeX symbols, and pass that table to [[AboxToLaTex][abox2latex]] with the '-t' switch. For example, [[AboxToLaTex][abox2latex]] uses the following default abbreviations table:

<verbatim>
	[
	  ["->"	, "\\ensuremath{\\rightarrow}"],
	  [ "\\/" , "\\ensuremath{\\vee}"],
	  [ "/\\" , "\\ensuremath{\\wedge}"],
	  [ "=="  , "\\ensuremath{\\equiv}"],
	  [ "++"  , "\\ensuremath{+\\kern-.4em+}"]
	]
</verbatim>

*Examples*

The location of boxenv.sty can be appended to your TEXINPUTS environment variable as follows:

For Bourne shells
<verbatim>
 # TEXINPUTS=<boxenv.sty location>:${TEXINPUTS}; export TEXINPUTS
</verbatim>

For C shells
<verbatim>
 # set TEXINPUTS=<boxenv.sty location>:${TEXINPUTS}; setenv TEXINPUTS
</verbatim>

Assuming that the generated LaTeX code is stored in the file example.tex, then a typical LaTeX document that includes the file example.tex looks like:

<verbatim>
 \documentstyle{article}
 \usepackage{boxenv}
 
 \begin{document}
 \input{example.tex}
 \enddocument}
</verbatim>

*Layout Preserving Pretty-Printing with GPP*

[[AboxToLaTex][Abox2latex]] can be used for layout preserving pretty-printing. To that end, you have to produce an abox term with [[AsFix2Abox][asfix2abox]] and pass it the '-c' switch to preserve layout in the [[BoxLanguage][Box]] expression. Then you use [[AboxToLaTex][abox2latex]] with the '--alltt' switch to produce a LaTeX alltt environment:

<verbatim>
 asfix2abox -c -i <your_file>.asfix \
 abox2latex --alltt -o <your_file>.tex
</verbatim>

Then you include the 'alltt' and 'boxenv' style files in your document, and input '&lt;your_file>.tex:

<verbatim>
 \documentclass{article}
 \usepackage{alltt}
 \usepackage{boxenv}

 \begin{document}
 \input{<your_file>.tex}
 \end{document}
</verbatim>



*See Also*

GenericPrettyPrinter, HowToPrettyPrintAGrammar, AboxToLaTex