picrin/lib/ext/compile.c

458 lines
11 KiB
C

/**
* See Copyright Notice in picrin.h
*/
#include "picrin.h"
#include "picrin/extra.h"
#include "../object.h"
#include "../state.h"
KHASH_DEFINE(env, struct identifier *, symbol *, kh_ptr_hash_func, kh_ptr_hash_equal)
pic_value
pic_make_env(pic_state *pic, pic_value prefix)
{
struct env *env;
env = (struct env *)pic_obj_alloc(pic, sizeof(struct env), PIC_TYPE_ENV);
env->up = NULL;
env->prefix = pic_str_ptr(pic, prefix);
kh_init(env, &env->map);
return obj_value(pic, env);
}
static pic_value
default_env(pic_state *pic)
{
return pic_ref(pic, "default-environment");
}
static pic_value
extend_env(pic_state *pic, pic_value up)
{
struct env *env;
env = (struct env *)pic_obj_alloc(pic, sizeof(struct env), PIC_TYPE_ENV);
env->up = pic_env_ptr(pic, up);
env->prefix = NULL;
kh_init(env, &env->map);
return obj_value(pic, env);
}
static bool
search_scope(pic_state *pic, pic_value id, pic_value env, pic_value *uid)
{
int it;
it = kh_get(env, &pic_env_ptr(pic, env)->map, pic_id_ptr(pic, id));
if (it == kh_end(&pic_env_ptr(pic, env)->map)) {
return false;
}
*uid = obj_value(pic, kh_val(&pic_env_ptr(pic, env)->map, it));
return true;
}
static bool
search(pic_state *pic, pic_value id, pic_value env, pic_value *uid)
{
struct env *e;
while (1) {
if (search_scope(pic, id, env, uid))
return true;
e = pic_env_ptr(pic, env)->up;
if (e == NULL)
break;
env = obj_value(pic, e);
}
return false;
}
pic_value
pic_find_identifier(pic_state *pic, pic_value id, pic_value env)
{
struct env *e;
pic_value uid;
while (! search(pic, id, env, &uid)) {
if (pic_sym_p(pic, id)) {
while (1) {
e = pic_env_ptr(pic, env);
if (e->up == NULL)
break;
env = obj_value(pic, e->up);
}
return pic_add_identifier(pic, id, env);
}
env = obj_value(pic, pic_id_ptr(pic, id)->env); /* do not overwrite id first */
id = obj_value(pic, pic_id_ptr(pic, id)->u.id);
}
return uid;
}
pic_value
pic_add_identifier(pic_state *pic, pic_value id, pic_value env)
{
const char *name, *prefix;
pic_value uid, str;
if (search_scope(pic, id, env, &uid)) {
return uid;
}
name = pic_str(pic, pic_id_name(pic, id), NULL);
if (pic_env_ptr(pic, env)->up == NULL && pic_sym_p(pic, id)) {
prefix = pic_str(pic, obj_value(pic, pic_env_ptr(pic, env)->prefix), NULL);
str = pic_strf_value(pic, "%s%s", prefix, name);
} else {
str = pic_strf_value(pic, ".%s.%d", name, pic->ucnt++);
}
uid = pic_intern(pic, str);
pic_set_identifier(pic, id, uid, env);
return uid;
}
void
pic_set_identifier(pic_state *pic, pic_value id, pic_value uid, pic_value env)
{
int it, ret;
it = kh_put(env, &pic_env_ptr(pic, env)->map, pic_id_ptr(pic, id), &ret);
kh_val(&pic_env_ptr(pic, env)->map, it) = pic_sym_ptr(pic, uid);
}
#define EQ(sym, lit) (strcmp(pic_sym(pic, sym), lit) == 0)
#define S(lit) (pic_intern_lit(pic, lit))
#define pic_sym(pic,sym) pic_str(pic, pic_sym_name(pic, (sym)), NULL)
static void
define_macro(pic_state *pic, pic_value uid, pic_value mac)
{
if (pic_dict_has(pic, pic->macros, uid)) {
pic_warnf(pic, "redefining syntax variable: %s", pic_sym(pic, uid));
}
pic_dict_set(pic, pic->macros, uid, mac);
}
static bool
find_macro(pic_state *pic, pic_value uid, pic_value *mac)
{
if (! pic_dict_has(pic, pic->macros, uid)) {
return false;
}
*mac = pic_dict_ref(pic, pic->macros, uid);
return true;
}
static void
shadow_macro(pic_state *pic, pic_value uid)
{
if (pic_dict_has(pic, pic->macros, uid)) {
pic_dict_del(pic, pic->macros, uid);
}
}
static pic_value expand(pic_state *, pic_value expr, pic_value env, pic_value deferred);
static pic_value expand_lambda(pic_state *, pic_value expr, pic_value env);
static pic_value
expand_var(pic_state *pic, pic_value id, pic_value env, pic_value deferred)
{
pic_value mac, functor;
functor = pic_find_identifier(pic, id, env);
if (find_macro(pic, functor, &mac)) {
return expand(pic, pic_call(pic, mac, 2, id, env), env, deferred);
}
return functor;
}
static pic_value
expand_quote(pic_state *pic, pic_value expr)
{
return pic_cons(pic, S("core#quote"), pic_cdr(pic, expr));
}
static pic_value
expand_list(pic_state *pic, pic_value obj, pic_value env, pic_value deferred)
{
size_t ai = pic_enter(pic);
pic_value x, head, tail;
if (pic_pair_p(pic, obj)) {
head = expand(pic, pic_car(pic, obj), env, deferred);
tail = expand_list(pic, pic_cdr(pic, obj), env, deferred);
x = pic_cons(pic, head, tail);
} else {
x = expand(pic, obj, env, deferred);
}
pic_leave(pic, ai);
pic_protect(pic, x);
return x;
}
static pic_value
expand_defer(pic_state *pic, pic_value expr, pic_value deferred)
{
pic_value skel = pic_cons(pic, pic_invalid_value(pic), pic_invalid_value(pic));
pic_set_car(pic, deferred, pic_cons(pic, pic_cons(pic, expr, skel), pic_car(pic, deferred)));
return skel;
}
static void
expand_deferred(pic_state *pic, pic_value deferred, pic_value env)
{
pic_value defer, val, src, dst, it;
deferred = pic_car(pic, deferred);
pic_for_each (defer, pic_reverse(pic, deferred), it) {
src = pic_car(pic, defer);
dst = pic_cdr(pic, defer);
val = expand_lambda(pic, src, env);
/* copy */
pic_set_car(pic, dst, pic_car(pic, val));
pic_set_cdr(pic, dst, pic_cdr(pic, val));
}
}
static pic_value
expand_lambda(pic_state *pic, pic_value expr, pic_value env)
{
pic_value formal, body;
pic_value in;
pic_value a, deferred;
in = extend_env(pic, env);
for (a = pic_cadr(pic, expr); pic_pair_p(pic, a); a = pic_cdr(pic, a)) {
pic_add_identifier(pic, pic_car(pic, a), in);
}
if (pic_id_p(pic, a)) {
pic_add_identifier(pic, a, in);
}
deferred = pic_list(pic, 1, pic_nil_value(pic));
formal = expand_list(pic, pic_list_ref(pic, expr, 1), in, deferred);
body = expand(pic, pic_list_ref(pic, expr, 2), in, deferred);
expand_deferred(pic, deferred, in);
return pic_list(pic, 3, S("core#lambda"), formal, body);
}
static pic_value
expand_define(pic_state *pic, pic_value expr, pic_value env, pic_value deferred)
{
pic_value uid, val;
uid = pic_add_identifier(pic, pic_list_ref(pic, expr, 1), env);
shadow_macro(pic, uid);
val = expand(pic, pic_list_ref(pic, expr, 2), env, deferred);
return pic_list(pic, 3, S("core#define"), uid, val);
}
static pic_value
expand_defmacro(pic_state *pic, pic_value expr, pic_value env)
{
pic_value uid, val;
uid = pic_add_identifier(pic, pic_list_ref(pic, expr, 1), env);
val = pic_load(pic, pic_compile(pic, pic_list_ref(pic, expr, 2), env));
if (! pic_proc_p(pic, val)) {
pic_error(pic, "macro definition evaluates to non-procedure object", 1, pic_list_ref(pic, expr, 1));
}
define_macro(pic, uid, val);
return pic_undef_value(pic);
}
static pic_value
expand_node(pic_state *pic, pic_value expr, pic_value env, pic_value deferred)
{
switch (pic_type(pic, expr)) {
case PIC_TYPE_ID:
case PIC_TYPE_SYMBOL: {
return expand_var(pic, expr, env, deferred);
}
case PIC_TYPE_PAIR: {
pic_value mac;
if (! pic_list_p(pic, expr)) {
pic_error(pic, "cannot expand improper list", 1, expr);
}
if (pic_id_p(pic, pic_car(pic, expr))) {
pic_value functor;
functor = pic_find_identifier(pic, pic_car(pic, expr), env);
if (EQ(functor, "core#define-macro")) {
return expand_defmacro(pic, expr, env);
}
else if (EQ(functor, "core#lambda")) {
return expand_defer(pic, expr, deferred);
}
else if (EQ(functor, "core#define")) {
return expand_define(pic, expr, env, deferred);
}
else if (EQ(functor, "core#quote")) {
return expand_quote(pic, expr);
}
if (find_macro(pic, functor, &mac)) {
return expand(pic, pic_call(pic, mac, 2, expr, env), env, deferred);
}
}
return expand_list(pic, expr, env, deferred);
}
default:
return expr;
}
}
static pic_value
expand(pic_state *pic, pic_value expr, pic_value env, pic_value deferred)
{
size_t ai = pic_enter(pic);
pic_value v;
v = expand_node(pic, expr, env, deferred);
pic_leave(pic, ai);
pic_protect(pic, v);
return v;
}
pic_value
pic_compile(pic_state *pic, pic_value expr, pic_value env)
{
pic_value v, deferred;
deferred = pic_list(pic, 1, pic_nil_value(pic));
v = expand(pic, expr, env, deferred);
expand_deferred(pic, deferred, env);
return v;
}
static pic_value
pic_compile_make_environment(pic_state *pic)
{
pic_value name;
pic_get_args(pic, "m", &name);
return pic_make_env(pic, pic_sym_name(pic, name));
}
static pic_value
pic_compile_set_identifier(pic_state *pic)
{
pic_value id, uid, env;
pic_get_args(pic, "omo", &id, &uid, &env);
TYPE_CHECK(pic, id, id);
TYPE_CHECK(pic, env, env);
pic_set_identifier(pic, id, uid, env);
return pic_undef_value(pic);
}
static pic_value
pic_compile_find_identifier(pic_state *pic)
{
pic_value id, env;
pic_get_args(pic, "oo", &id, &env);
TYPE_CHECK(pic, id, id);
TYPE_CHECK(pic, env, env);
return pic_find_identifier(pic, id, env);
}
static pic_value
pic_compile_add_macro(pic_state *pic)
{
pic_value id, mac, uid;
pic_get_args(pic, "ol", &id, &mac);
TYPE_CHECK(pic, id, id);
uid = pic_find_identifier(pic, id, default_env(pic));
define_macro(pic, uid, mac);
return pic_undef_value(pic);
}
static pic_value
pic_compile_compile(pic_state *pic)
{
pic_value program, env = default_env(pic);
pic_get_args(pic, "o|o", &program, &env);
TYPE_CHECK(pic, env, env);
return pic_compile(pic, program, env);
}
static pic_value
pic_compile_eval(pic_state *pic)
{
pic_value program, env = default_env(pic);
pic_get_args(pic, "o|o", &program, &env);
TYPE_CHECK(pic, env, env);
return pic_load(pic, pic_compile(pic, program, env));
}
#define add_keyword(name) do { \
pic_value var; \
var = pic_intern_lit(pic, name); \
pic_set_identifier(pic, var, var, env); \
} while (0)
void
pic_init_compile(pic_state *pic)
{
pic_value env = pic_make_env(pic, pic_lit_value(pic, ""));
add_keyword("core#define");
add_keyword("core#set!");
add_keyword("core#quote");
add_keyword("core#lambda");
add_keyword("core#if");
add_keyword("core#begin");
add_keyword("core#define-macro");
pic_define(pic, "default-environment", env);
pic_defun(pic, "make-environment", pic_compile_make_environment);
pic_defun(pic, "find-identifier", pic_compile_find_identifier);
pic_defun(pic, "set-identifier!", pic_compile_set_identifier);
pic_defun(pic, "add-macro!", pic_compile_add_macro);
pic_defun(pic, "compile", pic_compile_compile);
pic_defun(pic, "eval", pic_compile_eval);
}