R7RS-bridge Project
===================

R7RS-bridge project is a research project which aims to:

 - Prepare R6RS library which implements R7RS small language
 - Tryout R7RS small language by implementing various library

Non-Implemented Features
------------------------

- cond-expand
- port-open?, char-ready?, u8-ready?

Supported Implementation
------------------------

- nmosh / mosh ( http://github.com/higepon/mosh )

We use nmosh as a baseline interpreter.

- Vicare (0.2d3-1)
  Unsupported features: 
    load, repl

- Guile 2.x (2.0.3)
  Unsupported features: 
    load, repl
    cond-expand (SRFI-0)

- Petite Chez Scheme 8.x (8.4)
  Unsupported features: 
    load, repl
    get-environment-variables (SRFI-98)

- IronScheme (1.0 RC6)
  Unsupported features:
    load, repl
    Compile (pre-expand program/library)

- Sagittarius (0.2.2)
  Unsupported features:
    load, repl
    weak-vectors

- Larceny (0.98b1)
  Unsupported features:
    load with environment
    repl
    Compile (pre-expand program/library)
    char-ready? for string port
    u8-ready? for bytevector port

- (Other R6RS, except Racket)

Racket cannot use R6RS libraries without #!r6rs marker.
TODO: Test other R6RS impl and list here..

- "Patched" chibi-scheme ( https://github.com/okuoku/chibi-scheme )

Original chibi-scheme cannot recognize the file with ".sls" extension as a
library.


How to use
----------

 - MOSH -

   nmosh --loadpath=lib-r6rs:lib SCRIPT.SPS

 - VICARE -

   vicare -L lib-r6rs -L lib SCRIPT.SPS
   (--r6rs-repl SCRIPT.SPS needed under some circumstances..)

 - GUILE -

   guile -l load/guile.scm SCRIPT.SPS

 - CHEZ SCHEME -

   petite --libdirs lib-r6rs:lib --libext sls --program SCRIPT.SPS

   In Win32, use --libdirs lib-r6rs;lib (semicolon)

 - IronScheme -

   IronScheme.Console.exe load/ironscheme.scm SCRIPT.SPS

 - Sagittarius Scheme -

   sash -Llib-r6rs -Llib -Lload/sagittarius SCRIPT.SPS

 - Larceny -

   larceny -r6rs -path lib-r6rs:lib -program SCRIPT.SPS

   In Win32, use --libdirs lib-r6rs;lib (semicolon)

 - Patched chibi-scheme -

   chibi-scheme -Ilib SCRIPT.SPS


Library format
--------------

"R7RS-bridge" formatted libraries are valid R6RS library with R7RS friendly
structure.

   (library (example library)
            (export func)
            (import (scheme base)
                    (another library))
            (begin
               ;;; Library content ....

               ))

Note that the "export - import - begin" sequence is mandatory for compatibility
with R7RS. (ie. don't forget to add a begin around library body...)

In this format, just replacing s/library/define-library/ will create valid
R7RS library.

In library entry, you cannot use R6RS-only reader syntax. Namely:

   Bytevectors:   #vu8( ... ) notation is not supported by R7RS.
   Flags:         #!r6rs ...
   Syntax, Quasi-syntax: #'...


R6RS Backend Libraries
----------------------

surfage - win32 patched version of Surfage library.

 Source : https://github.com/dharmatech/surfage
 License: Checking (BSD like)


TESTS
-----

chibi-scheme - chibi-scheme R7RS tests
 Source : chibi-scheme
 License: Unknown. (chibi-scheme + R7RS)

laceny-R6RS - R6RS benchmarks
 Source : (Larceny)
 License: Unknown.