nyacc version 0.71.0 released

[Matt Wette]

nyacc version 0.71.0 is released as beta

nyacc is a LALR parser generator written from the ground up in guile

Features/Updates:

* clean scheme-flavored syntax for grammar specification

* prototype parsers for C99,(partial) _javascript_, matlab that output parse trees in a SXML format

* update: C99 preprocessor updated to expand defines in C code

* update: cleaned up file structure

* update: started working on test-suite

* update: added grammar for C++

* update: build parsers via bison

  + to use in example below replace `make-lalr-machine' with `make-lalr-machine/bison’,

     after adding (use-module (nyacc bison)

  + the bison module will 

     - export a bison gram.y file, 

     - run "bison -x gram.y” to produce a gram.xml file

     - translate gram.xml file into the nyacc “machine” data structure

  

To run a simple demo:

$ tar xzf nyacc-0.71.tar.gz

$ cd examples/nyacc/lang/calc

$ ./calc

2 + 2 => 4

Tcalc.scm:

(use-modules (nyacc lalr))

(use-modules (nyacc lex))

(use-modules (nyacc parse))

(define simple-spec

  (lalr-spec

   (prec< (left "+" "-") (left "*" "/"))

   (start expr)

   (grammar

    (expr

     (expr "+" expr ($$ (+ $1 $3)))

     (expr "-" expr ($$ (- $1 $3)))

     (expr "*" expr ($$ (* $1 $3)))

     (expr "/" expr ($$ (/ $1 $3)))

     ($fixed ($$ (string->number $1)))

     ($float ($$ (string->number $1)))

     ("(" expr ")" ($$ $2))))))

(define simple-mach (make-lalr-machine simple-spec))

(define match-table (assq-ref simple-mach 'mtab))

(define gen-lexer (make-lexer-generator match-table))

(define parse (make-lalr-parser simple-mach))

(define demo-string "2 + 2")

(simple-format #t "~A => ~A\n"

      demo-string

      (with-input-from-string demo-string

(lambda () (parse (gen-lexer)))))

download tarball from:

http://download.savannah.gnu.org/releases/nyacc/

or git clone from

git://git.savannah.nongnu.org/nyacc.git