R6rs NPM | npm.io

r6rs

A Scheme interpreter (Currently partly R6RS compliant)

This program is still work in progress! Use it on your own risk!

Usage

npm install r6rs will do the trick.

import { Machine } from 'r6rs';
let machine = new Machine();
console.log(machine.evaluate('(+ 3 3)')); // NumberValue {value: 6}

Manually calling with AST

import { tokenize, parse, Machine } from 'r6rs';
let machine = new Machine();
console.log(machine.evaluate(expand(parse(tokenize('(+ 3 3)')), machine.expanderRoot))); // NumberValue {value: 6}
// Note that you can skip expand phase if you don't want to use macro expansion
// (Which includes let, letrec, and, ...)

Using native functions

import { Machine, NativeProcedureValue, PairValue } from 'r6rs';
let machine = new Machine();
machine.loadLibrary([
  new NativeProcedureValue('alert', list => {
    alert(list.car.value);
    return new PairValue();
  })
]);
console.log(machine.evaluate('(alert "Hello, world!")')); // ()

Using REPL

npm install r6rs -g then r6rs will do the trick. :)

Implementation status

R6RS specification

Types

Boolean
Number (Only real numbers are supported for now)
Character
Vector
String
Symbol
Pair (List)
Procedure
Bytevector
Abbreviations (Not a type though)

Number

Complex number
Real (decimal) number
Rational number
Integer number
NaN, infinity support

Library

Library syntax support

Base library

define, define-syntax
quote, quasiquote, unquote
lambda, if, set!
cond, case (Only cond is supported)
and, or
let, let*, letrec, letrec*, let-values, let*-values (only let, let* can be used due to lack of hygiene)
begin
eqv?, eq?, equal?
(type name)?
(type name)->(type name) (number->string doesn't support precision yet)
Rational number arithmetic operations (numerator, denominator, exact?, ...)
Real number arithmetic operations
Complex number arithmetic operations (make-rectangular, ...)
Boolean operations
Pair and list operations
Symbol operations
Character operations
String operations
Vector operations
Errors and violations
Control features (no call/cc yet)
Iteration let
let-syntax, letrec-syntax (not correctly implemented)
syntax-rules (Hygienic use is not supported yet)
identifier-syntax