ragel-julia: A C++ repository from dcjones

This is a fork of ragel that adds a Julia backend to the yet unreleased ragel 7.0.

To build, you will need version 0.12.0 of colm.

The resulting Julia code relies on goto expressions, which are not yet in Julia, but I have a pull request that adds them: JuliaLang/julia#5699.

It also relies on the (Switch)[https://github.com/dcjones/Switch.jl] package that adds C-style switch statements to Julia. That also uses gotos so its not yet available from the package manager.

Here's a quick example:

using Switch

%%{
    machine Test1;

    action dgt      { @printf("DGT: %c\n", fc); }
    action dec      { @printf("DEC: .\n"); }
    action exp      { @printf("EXP: %c\n", fc); }
    action exp_sign { @printf("SGN: %c\n", fc); }
    action number   { println("NUMBER") }

    number = (
        [0-9]+ $dgt ( '.' @dec [0-9]+ $dgt )?
        ( [eE] ( [+\-] $exp_sign )? [0-9]+ $exp )?
    ) %number;

    main := ( number '\n' )*;
}%%


function parse(data::String)
    p = 0
    pe = length(data)
    %% write data;
    %% write init;
    %% write exec;
end

parse("1234.56")

Saving the above as number.rl and running ragel -U number.rl" will generate a file number.jl`, which is very efficient, pure Julia number parser.

                 Ragel State Machine Compiler -- README
                 ======================================

Build Requirements

Make
g++

If you would like to modify Ragel and need to build Ragel's scanners and parsers from the specifications then set "build_parsers=yes" the DIST file and reconfigure. This variable is normally set to "no" in the distribution tarballs and "yes" in version control. You will need the following programs:

ragel (the most recent version)
kelbt (the most recent version)

To build the user guide set "build_manual=yes" in the DIST file and reconfigure. You will need the following extra programs:

fig2dev
pdflatex

Compilation and Installation

Ragel uses autoconf and automake.

$ ./configure --prefix=PREFIX $ make $ make install

dcjones/ragel-julia