lisp-game-jam/js-runtime/reflect.js
2024-04-26 14:30:59 -04:00

710 lines
26 KiB
JavaScript

// -*- js2-basic-offset: 4 -*-
class Char {
constructor(codepoint) {
this.codepoint = codepoint;
}
toString() {
let ch = String.fromCodePoint(this.codepoint);
if (ch.match(/[a-zA-Z0-9$[\]().]/)) return `#\\${ch}`;
return `#\\x${this.codepoint.toString(16)}`;
}
}
class Eof { toString() { return "#<eof>"; } }
class Nil { toString() { return "#nil"; } }
class Null { toString() { return "()"; } }
class Unspecified { toString() { return "#<unspecified>"; } }
class Complex {
constructor(real, imag) {
this.real = real;
this.imag = imag;
}
toString() {
const sign = this.imag >= 0 && Number.isFinite(this.imag) ? "+": "";
return `${flonum_to_string(this.real)}${sign}${flonum_to_string(this.imag)}i`;
}
}
class Fraction {
constructor(num, denom) {
this.num = num;
this.denom = denom;
}
toString() {
return `${this.num}/${this.denom}`;
}
}
class HeapObject {
constructor(reflector, obj) {
this.reflector = reflector;
this.obj = obj;
}
repr() { return this.toString(); } // Default implementation.
}
class Pair extends HeapObject {
toString() { return "#<pair>"; }
repr() {
let car_repr = repr(this.reflector.car(this));
let cdr_repr = repr(this.reflector.cdr(this));
if (cdr_repr == '()')
return `(${car_repr})`;
if (cdr_repr.charAt(0) == '(')
return `(${car_repr} ${cdr_repr.substring(1)}`;
return `(${car_repr} . ${cdr_repr})`;
}
}
class MutablePair extends Pair { toString() { return "#<mutable-pair>"; } }
class Vector extends HeapObject {
toString() { return "#<vector>"; }
repr() {
let len = this.reflector.vector_length(this);
let out = '#(';
for (let i = 0; i < len; i++) {
if (i) out += ' ';
out += repr(this.reflector.vector_ref(this, i));
}
out += ')';
return out;
}
}
class MutableVector extends Vector {
toString() { return "#<mutable-vector>"; }
}
class Bytevector extends HeapObject {
toString() { return "#<bytevector>"; }
repr() {
let len = this.reflector.bytevector_length(this);
let out = '#vu8(';
for (let i = 0; i < len; i++) {
if (i) out += ' ';
out += this.reflector.bytevector_ref(this, i);
}
out += ')';
return out;
}
}
class MutableBytevector extends Bytevector {
toString() { return "#<mutable-bytevector>"; }
}
class Bitvector extends HeapObject {
toString() { return "#<bitvector>"; }
repr() {
let len = this.reflector.bitvector_length(this);
let out = '#*';
for (let i = 0; i < len; i++) {
out += this.reflector.bitvector_ref(this, i) ? '1' : '0';
}
return out;
}
}
class MutableBitvector extends Bitvector {
toString() { return "#<mutable-bitvector>"; }
}
class MutableString extends HeapObject {
toString() { return "#<mutable-string>"; }
repr() { return string_repr(this.reflector.string_value(this)); }
}
class Procedure extends HeapObject {
toString() { return "#<procedure>"; }
call(...arg) {
return this.reflector.call(this, ...arg);
}
}
class Sym extends HeapObject {
toString() { return "#<symbol>"; }
repr() { return this.reflector.symbol_name(this); }
}
class Keyword extends HeapObject {
toString() { return "#<keyword>"; }
repr() { return `#:${this.reflector.keyword_name(this)}`; }
}
class Variable extends HeapObject { toString() { return "#<variable>"; } }
class AtomicBox extends HeapObject { toString() { return "#<atomic-box>"; } }
class HashTable extends HeapObject { toString() { return "#<hash-table>"; } }
class WeakTable extends HeapObject { toString() { return "#<weak-table>"; } }
class Fluid extends HeapObject { toString() { return "#<fluid>"; } }
class DynamicState extends HeapObject { toString() { return "#<dynamic-state>"; } }
class Syntax extends HeapObject { toString() { return "#<syntax>"; } }
class Port extends HeapObject { toString() { return "#<port>"; } }
class Struct extends HeapObject { toString() { return "#<struct>"; } }
function instantiate_streaming(path, imports) {
if (typeof fetch !== 'undefined')
return WebAssembly.instantiateStreaming(fetch(path), imports);
let bytes;
if (typeof read !== 'undefined') {
bytes = read(path, 'binary');
} else if (typeof readFile !== 'undefined') {
bytes = readFile(path);
} else {
let fs = require('fs');
bytes = fs.readFileSync(path);
}
return WebAssembly.instantiate(bytes, imports);
}
class Scheme {
#instance;
#abi;
constructor(instance, abi) {
this.#instance = instance;
this.#abi = abi;
}
static async reflect(abi) {
let debug = {
debug_str(x) { console.log(`reflect debug: ${x}`); },
debug_str_i32(x, y) { console.log(`reflect debug: ${x}: ${y}`); },
debug_str_scm: (x, y) => {
console.log(`reflect debug: ${x}: #<scm>`);
},
};
let { module, instance } =
await instantiate_streaming('js-runtime/reflect.wasm', {
abi,
debug,
rt: {
die(tag, data) { throw new SchemeTrapError(tag, data); },
wtf8_to_string(wtf8) { return wtf8_to_string(wtf8); },
string_to_wtf8(str) { return string_to_wtf8(str); },
}
});
return new Scheme(instance, abi);
}
#init_module(mod) {
mod.set_debug_handler({
debug_str(x) { console.log(`debug: ${x}`); },
debug_str_i32(x, y) { console.log(`debug: ${x}: ${y}`); },
debug_str_scm: (x, y) => {
console.log(`debug: ${x}: ${repr(this.#to_js(y))}`);
},
});
mod.set_ffi_handler({
procedure_to_extern: (obj) => {
const proc = this.#to_js(obj);
return (...args) => {
return proc.call(...args);
};
}
});
let proc = new Procedure(this, mod.get_export('$load').value);
return proc.call();
}
static async load_main(path, abi, user_imports = {}) {
let mod = await SchemeModule.fetch_and_instantiate(path, abi, user_imports);
let reflect = await mod.reflect();
return reflect.#init_module(mod);
}
async load_extension(path, user_imports = {}) {
let mod = await SchemeModule.fetch_and_instantiate(path, this.#abi, user_imports);
return this.#init_module(mod);
}
#to_scm(js) {
let api = this.#instance.exports;
if (typeof(js) == 'number') {
return api.scm_from_f64(js);
} else if (typeof(js) == 'bigint') {
if (BigInt(api.scm_most_negative_fixnum()) <= js
&& js <= BigInt(api.scm_most_positive_fixnum()))
return api.scm_from_fixnum(Number(js));
return api.scm_from_bignum(js);
} else if (typeof(js) == 'boolean') {
return js ? api.scm_true() : api.scm_false();
} else if (typeof(js) == 'string') {
return api.scm_from_string(js);
} else if (typeof(js) == 'object') {
if (js instanceof Eof) return api.scm_eof();
if (js instanceof Nil) return api.scm_nil();
if (js instanceof Null) return api.scm_null();
if (js instanceof Unspecified) return api.scm_unspecified();
if (js instanceof Char) return api.scm_from_char(js.codepoint);
if (js instanceof HeapObject) return js.obj;
if (js instanceof Fraction)
return api.scm_from_fraction(this.#to_scm(js.num),
this.#to_scm(js.denom));
if (js instanceof Complex)
return api.scm_from_complex(js.real, js.imag);
return api.scm_from_extern(js);
} else {
throw new Error(`unexpected; ${typeof(js)}`);
}
}
#to_js(scm) {
let api = this.#instance.exports;
let descr = api.describe(scm);
let handlers = {
fixnum: () => BigInt(api.fixnum_value(scm)),
char: () => new Char(api.char_value(scm)),
true: () => true,
false: () => false,
eof: () => new Eof,
nil: () => new Nil,
null: () => new Null,
unspecified: () => new Unspecified,
flonum: () => api.flonum_value(scm),
bignum: () => api.bignum_value(scm),
complex: () => new Complex(api.complex_real(scm),
api.complex_imag(scm)),
fraction: () => new Fraction(this.#to_js(api.fraction_num(scm)),
this.#to_js(api.fraction_denom(scm))),
pair: () => new Pair(this, scm),
'mutable-pair': () => new MutablePair(this, scm),
vector: () => new Vector(this, scm),
'mutable-vector': () => new MutableVector(this, scm),
bytevector: () => new Bytevector(this, scm),
'mutable-bytevector': () => new MutableBytevector(this, scm),
bitvector: () => new Bitvector(this, scm),
'mutable-bitvector': () => new MutableBitvector(this, scm),
string: () => api.string_value(scm),
'mutable-string': () => new MutableString(this, scm),
procedure: () => new Procedure(this, scm),
symbol: () => new Sym(this, scm),
keyword: () => new Keyword(this, scm),
variable: () => new Variable(this, scm),
'atomic-box': () => new AtomicBox(this, scm),
'hash-table': () => new HashTable(this, scm),
'weak-table': () => new WeakTable(this, scm),
fluid: () => new Fluid(this, scm),
'dynamic-state': () => new DynamicState(this, scm),
syntax: () => new Syntax(this, scm),
port: () => new Port(this, scm),
struct: () => new Struct(this, scm),
'extern-ref': () => api.extern_value(scm)
};
let handler = handlers[descr];
return handler ? handler() : scm;
}
call(func, ...args) {
let api = this.#instance.exports;
let argv = api.make_vector(args.length + 1, api.scm_false());
func = this.#to_scm(func);
api.vector_set(argv, 0, func);
for (let [idx, arg] of args.entries())
api.vector_set(argv, idx + 1, this.#to_scm(arg));
argv = api.call(func, argv);
let results = [];
for (let idx = 0; idx < api.vector_length(argv); idx++)
results.push(this.#to_js(api.vector_ref(argv, idx)))
return results;
}
car(x) { return this.#to_js(this.#instance.exports.car(x.obj)); }
cdr(x) { return this.#to_js(this.#instance.exports.cdr(x.obj)); }
vector_length(x) { return this.#instance.exports.vector_length(x.obj); }
vector_ref(x, i) {
return this.#to_js(this.#instance.exports.vector_ref(x.obj, i));
}
bytevector_length(x) {
return this.#instance.exports.bytevector_length(x.obj);
}
bytevector_ref(x, i) {
return this.#instance.exports.bytevector_ref(x.obj, i);
}
bitvector_length(x) {
return this.#instance.exports.bitvector_length(x.obj);
}
bitvector_ref(x, i) {
return this.#instance.exports.bitvector_ref(x.obj, i) == 1;
}
string_value(x) { return this.#instance.exports.string_value(x.obj); }
symbol_name(x) { return this.#instance.exports.symbol_name(x.obj); }
keyword_name(x) { return this.#instance.exports.keyword_name(x.obj); }
}
class SchemeTrapError extends Error {
constructor(tag, data) { super(); this.tag = tag; this.data = data; }
// FIXME: data is raw Scheme object; would need to be reflected to
// have a toString.
toString() { return `SchemeTrap(${this.tag}, <data>)`; }
}
function string_repr(str) {
// FIXME: Improve to match Scheme.
return '"' + str.replace(/(["\\])/g, '\\$1').replace(/\n/g, '\\n') + '"';
}
function flonum_to_string(f64) {
if (Object.is(f64, -0)) {
return '-0.0';
} else if (Number.isFinite(f64)) {
let repr = f64 + '';
return /^-?[0-9]+$/.test(repr) ? repr + '.0' : repr;
} else if (Number.isNaN(f64)) {
return '+nan.0';
} else {
return f64 < 0 ? '-inf.0' : '+inf.0';
}
}
let wtf8_helper;
function wtf8_to_string(wtf8) {
let { as_iter, iter_next } = wtf8_helper.exports;
let codepoints = [];
let iter = as_iter(wtf8);
for (let cp = iter_next(iter); cp != -1; cp = iter_next(iter))
codepoints.push(cp);
// Passing too many codepoints can overflow the stack.
let maxcp = 100000;
if (codepoints.length <= maxcp) {
return String.fromCodePoint(...codepoints);
}
// For converting large strings, concatenate several smaller
// strings.
let substrings = [];
let end = 0;
for (let start = 0; start != codepoints.length; start = end) {
end = Math.min(start + maxcp, codepoints.length);
substrings.push(String.fromCodePoint(...codepoints.slice(start, end)));
}
return substrings.join('');
}
function string_to_wtf8(str) {
let { string_builder, builder_push_codepoint, finish_builder } =
wtf8_helper.exports;
let builder = string_builder()
for (let cp of str)
builder_push_codepoint(builder, cp.codePointAt(0));
return finish_builder(builder);
}
async function load_wtf8_helper_module() {
if (wtf8_helper) return;
let { module, instance } = await instantiate_streaming("js-runtime/wtf8.wasm");
wtf8_helper = instance;
}
class SchemeModule {
#instance;
#io_handler;
#debug_handler;
#ffi_handler;
static #rt = {
bignum_from_string(str) { return BigInt(str); },
bignum_from_i32(n) { return BigInt(n); },
bignum_from_i64(n) { return n; },
bignum_from_u64(n) { return n < 0n ? 0xffff_ffff_ffff_ffffn + (n + 1n) : n; },
bignum_is_i64(n) {
return -0x8000_0000_0000_0000n <= n && n <= 0x7FFF_FFFF_FFFF_FFFFn;
},
bignum_is_u64(n) {
return 0n <= n && n <= 0xFFFF_FFFF_FFFF_FFFFn;
},
// This truncates; see https://tc39.es/ecma262/#sec-tobigint64.
bignum_get_i64(n) { return n; },
bignum_add(a, b) { return BigInt(a) + BigInt(b) },
bignum_sub(a, b) { return BigInt(a) - BigInt(b) },
bignum_mul(a, b) { return BigInt(a) * BigInt(b) },
bignum_lsh(a, b) { return BigInt(a) << BigInt(b) },
bignum_rsh(a, b) { return BigInt(a) >> BigInt(b) },
bignum_quo(a, b) { return BigInt(a) / BigInt(b) },
bignum_rem(a, b) { return BigInt(a) % BigInt(b) },
bignum_mod(a, b) {
let r = BigInt(a) % BigInt(b);
if ((b > 0n && r < 0n) || (b < 0n && r > 0n)) {
return b + r;
} else {
return r;
}
},
bignum_gcd(a, b) {
a = BigInt(a);
b = BigInt(b);
if (a < 0n) { a = -a; }
if (b < 0n) { b = -b; }
if (a == 0n) { return b; }
if (b == 0n) { return a; }
let r;
while (b != 0n) {
r = a % b;
a = b;
b = r;
}
return a;
},
bignum_logand(a, b) { return BigInt(a) & BigInt(b); },
bignum_logior(a, b) { return BigInt(a) | BigInt(b); },
bignum_logxor(a, b) { return BigInt(a) ^ BigInt(b); },
bignum_logsub(a, b) { return BigInt(a) & (~ BigInt(b)); },
bignum_lt(a, b) { return a < b; },
bignum_le(a, b) { return a <= b; },
bignum_eq(a, b) { return a == b; },
bignum_to_f64(n) { return Number(n); },
f64_is_nan(n) { return Number.isNaN(n); },
f64_is_infinite(n) { return !Number.isFinite(n); },
flonum_to_string,
string_upcase: Function.call.bind(String.prototype.toUpperCase),
string_downcase: Function.call.bind(String.prototype.toLowerCase),
make_weak_map() { return new WeakMap; },
weak_map_get(map, k, fail) {
const val = map.get(k);
return val === undefined ? fail: val;
},
weak_map_set(map, k, v) { return map.set(k, v); },
weak_map_delete(map, k) { return map.delete(k); },
fsqrt: Math.sqrt,
fsin: Math.sin,
fcos: Math.cos,
ftan: Math.tan,
fasin: Math.asin,
facos: Math.acos,
fatan: Math.atan,
fatan2: Math.atan2,
flog: Math.log,
fexp: Math.exp,
jiffies_per_second() { return 1000000; },
current_jiffy() { return performance.now() * 1000; },
current_second() { return Date.now() / 1000; },
// Wrap in functions to allow for lazy loading of the wtf8
// module.
wtf8_to_string(wtf8) { return wtf8_to_string(wtf8); },
string_to_wtf8(str) { return string_to_wtf8(str); },
die(tag, data) { throw new SchemeTrapError(tag, data); }
};
constructor(instance) {
this.#instance = instance;
if (typeof printErr === 'function') { // v8/sm dev console
// On the console, try to use 'write' (v8) or 'putstr' (sm),
// as these don't add an extraneous newline. Unfortunately
// JSC doesn't have a printer that doesn't add a newline.
let write_no_newline =
typeof write === 'function' ? write
: typeof putstr === 'function' ? putstr : print;
// Use readline when available. v8 strips newlines so
// we need to add them back.
let read_stdin =
typeof readline == 'function' ? () => {
let line = readline();
if (line) {
return `${line}\n`;
} else {
return '\n';
}
}: () => '';
let delete_file = (filename) => false;
this.#io_handler = {
write_stdout: write_no_newline,
write_stderr: printErr,
read_stdin,
file_exists: (filename) => false,
open_input_file: (filename) => {},
open_output_file: (filename) => {},
close_file: () => undefined,
read_file: (handle, length) => 0,
write_file: (handle, length) => 0,
seek_file: (handle, offset, whence) => -1,
file_random_access: (handle) => false,
file_buffer_size: (handle) => 0,
file_buffer_ref: (handle, i) => 0,
file_buffer_set: (handle, i, x) => undefined,
delete_file: (filename) => undefined
};
} else if (typeof window !== 'undefined') { // web browser
this.#io_handler = {
write_stdout: console.log,
write_stderr: console.error,
read_stdin: () => '',
file_exists: (filename) => false,
open_input_file: (filename) => {},
open_output_file: (filename) => {},
close_file: () => undefined,
read_file: (handle, length) => 0,
write_file: (handle, length) => 0,
seek_file: (handle, offset, whence) => -1,
file_random_access: (handle) => false,
file_buffer_size: (handle) => 0,
file_buffer_ref: (handle, i) => 0,
file_buffer_set: (handle, i, x) => undefined,
delete_file: (filename) => undefined
};
} else { // nodejs
const fs = require('fs');
const process = require('process');
const bufLength = 1024;
const stdinBuf = Buffer.alloc(bufLength);
const SEEK_SET = 0, SEEK_CUR = 1, SEEK_END = 2;
this.#io_handler = {
write_stdout: console.log,
write_stderr: console.error,
read_stdin: () => {
let n = fs.readSync(process.stdin.fd, stdinBuf, 0, stdinBuf.length);
return stdinBuf.toString('utf8', 0, n);
},
file_exists: fs.existsSync.bind(fs),
open_input_file: (filename) => {
let fd = fs.openSync(filename, 'r');
return {
fd,
buf: Buffer.alloc(bufLength),
pos: 0
};
},
open_output_file: (filename) => {
let fd = fs.openSync(filename, 'w');
return {
fd,
buf: Buffer.alloc(bufLength),
pos: 0
};
},
close_file: (handle) => {
fs.closeSync(handle.fd);
},
read_file: (handle, count) => {
const n = fs.readSync(handle.fd, handle.buf, 0, count, handle.pos);
handle.pos += n;
return n;
},
write_file: (handle, count) => {
const n = fs.writeSync(handle.fd, handle.buf, 0, count, handle.pos);
handle.pos += n;
return n;
},
seek_file: (handle, offset, whence) => {
// There doesn't seem to be a way to ask NodeJS if
// a position is valid or not.
if (whence == SEEK_SET) {
handle.pos = offset;
return handle.pos;
} else if (whence == SEEK_CUR) {
handle.pos += offset;
return handle.pos;
}
// SEEK_END not supported.
return -1;
},
file_random_access: (handle) => {
return true;
},
file_buffer_size: (handle) => {
return handle.buf.length;
},
file_buffer_ref: (handle, i) => {
return handle.buf[i];
},
file_buffer_set: (handle, i, x) => {
handle.buf[i] = x;
},
delete_file: fs.rmSync.bind(fs)
};
}
this.#debug_handler = {
debug_str(x) { console.log(`debug: ${x}`); },
debug_str_i32(x, y) { console.log(`debug: ${x}: ${y}`); },
debug_str_scm(x, y) { console.log(`debug: ${x}: #<scm>`); },
};
}
static async fetch_and_instantiate(path, imported_abi, user_imports = {}) {
await load_wtf8_helper_module();
let io = {
write_stdout(str) { mod.#io_handler.write_stdout(str); },
write_stderr(str) { mod.#io_handler.write_stderr(str); },
read_stdin() { return mod.#io_handler.read_stdin(); },
file_exists(filename) { return mod.#io_handler.file_exists(filename); },
open_input_file(filename) { return mod.#io_handler.open_input_file(filename); },
open_output_file(filename) { return mod.#io_handler.open_output_file(filename); },
close_file(handle) { mod.#io_handler.close_file(handle); },
read_file(handle, length) { return mod.#io_handler.read_file(handle, length); },
write_file(handle, length) { return mod.#io_handler.write_file(handle, length); },
seek_file(handle, offset, whence) { return mod.#io_handler.seek_file(handle, offset, whence); },
file_random_access(handle) { return mod.#io_handler.file_random_access(handle); },
file_buffer_size(handle) { return mod.#io_handler.file_buffer_size(handle); },
file_buffer_ref(handle, i) { return mod.#io_handler.file_buffer_ref(handle, i); },
file_buffer_set(handle, i, x) { return mod.#io_handler.file_buffer_set(handle, i, x); },
delete_file(filename) { mod.#io_handler.delete_file(filename); }
};
let debug = {
debug_str(x) { mod.#debug_handler.debug_str(x); },
debug_str_i32(x, y) { mod.#debug_handler.debug_str_i32(x, y); },
debug_str_scm(x, y) { mod.#debug_handler.debug_str_scm(x, y); },
}
let ffi = {
procedure_to_extern(proc) {
return mod.#ffi_handler.procedure_to_extern(proc);
}
};
let imports = {
rt: SchemeModule.#rt,
abi: imported_abi,
debug, io, ffi, ...user_imports
};
let { module, instance } = await instantiate_streaming(path, imports);
let mod = new SchemeModule(instance);
return mod;
}
set_io_handler(h) { this.#io_handler = h; }
set_debug_handler(h) { this.#debug_handler = h; }
set_ffi_handler(h) { this.#ffi_handler = h; }
all_exports() { return this.#instance.exports; }
exported_abi() {
let abi = {}
for (let [k, v] of Object.entries(this.all_exports())) {
if (k.startsWith("$"))
abi[k] = v;
}
return abi;
}
exports() {
let ret = {}
for (let [k, v] of Object.entries(this.all_exports())) {
if (!k.startsWith("$"))
ret[k] = v;
}
return ret;
}
get_export(name) {
if (name in this.all_exports())
return this.all_exports()[name];
throw new Error(`unknown export: ${name}`)
}
async reflect() {
return await Scheme.reflect(this.exported_abi());
}
}
function repr(obj) {
if (obj instanceof HeapObject)
return obj.repr();
if (typeof obj === 'boolean')
return obj ? '#t' : '#f';
if (typeof obj === 'number')
return flonum_to_string(obj);
if (typeof obj === 'string')
return string_repr(obj);
return obj + '';
}