rlp10/gribble

Text pre-processing in Gerbil Scheme

Gribble

Gribble is a text preprocessor written in Gerbil Scheme.

It consists of a library, which can be used be other Gerbil programs, as well as an executable program which can be used to process text files.

It is currently pre-alpha software. Nothing works here yet.

Syntax

The syntax is inspired by Scribble, the document processing software included as part of Racket. It uses a tilde ("~"), rather than an arobase ("@") so as to interfere less frequently with typical writing.

Generally, the markup is processed as scheme and, if the return is not void, then the original input text is replaced with the output. For example, all the following would output "Hello WORLD!":

;; Everything in brackets is run as Scheme
Hello ~(upcase "world")! 

;; A function that takes one or more strings can be called with
curly brackets
Hello ~upcase{world}!

;; A function can be given arguments other than strings using
square brackets
Hello ~upcase["world"]!

;; You can combine square and curly braces for functions taking
multiple arguments
Hello ~upcase["wor"]{ld}!

In the above example, upcase is a function which takes one or more strings, converts them to upper case and then appends them together.

Roadmap

• Produce a function "preprocess" that takes a string and outputs a string, implementing each of the syntax types above

• Write preprocess-file which takes a path, rather than a string

• Give preprocess an optional keyword argument which changes the special character "~" to something else.

• Produce a helper functions, "include" which includes and preprocesses another file by either a relative or absolute path

• Produce a command line program "gribble" which runs the preprocess function from the command-line, using standard input and output

• Update the command line program to take an optional argument changing the special character

Future Development Ideas

• Add metadata to documents

• Add functions for creating documentation, to be output to HTML

• Allow conversion of documents to PDF, through LaTeX