mes/mes.c
Jan Nieuwenhuizen 1684564ea1 Flip sign of cached symbols: only search cache if symbol is cached.
* mes.c (cache_save): Flip sign when caching and invalidating.
  (cache_invalidate): Flip sign when invalidating.
2016-10-21 20:44:18 +02:00

1573 lines
35 KiB
C

/* -*-comment-start: "//";comment-end:""-*-
* Mes --- Maxwell Equations of Software
* Copyright © 2016 Jan Nieuwenhuizen <janneke@gnu.org>
*
* This file is part of Mes.
*
* Mes is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 3 of the License, or (at
* your option) any later version.
*
* Mes is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with Mes. If not, see <http://www.gnu.org/licenses/>.
*/
#define STRING_MAX 2048
#define _GNU_SOURCE
#include <assert.h>
#include <ctype.h>
#include <limits.h>
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <stdbool.h>
#define DEBUG 0
#define BUILTIN_QUASIQUOTE 1 // 6x speedup for mescc
#define MES_FULL 1
enum type {CHAR, MACRO, NUMBER, PAIR, SCM, STRING, SYMBOL, VALUES, VECTOR,
FUNCTION0, FUNCTION1, FUNCTION2, FUNCTION3, FUNCTIONn};
struct scm_t;
typedef struct scm_t* (*function0_t) (void);
typedef struct scm_t* (*function1_t) (struct scm_t*);
typedef struct scm_t* (*function2_t) (struct scm_t*, struct scm_t*);
typedef struct scm_t* (*function3_t) (struct scm_t*, struct scm_t*, struct scm_t*);
typedef struct scm_t* (*functionn_t) (struct scm_t*);
typedef struct scm_t {
enum type type;
union {
char const *name;
struct scm_t* car;
int length;
};
union {
int value;
function0_t function0;
function1_t function1;
function2_t function2;
function3_t function3;
functionn_t functionn;
struct scm_t* cdr;
struct scm_t* macro;
struct scm_t** vector;
};
} scm;
scm temp_number = {NUMBER, .name="nul", .value=0};
#define MES_C 1
#include "mes.h"
scm *display_ (FILE* f, scm *x); //internal
scm *display_helper (FILE*, scm*, bool, char const*, bool);
scm scm_nil = {SCM, "()"};
scm scm_dot = {SCM, "."};
scm scm_f = {SCM, "#f"};
scm scm_t = {SCM, "#t"};
scm scm_undefined = {SCM, "*undefined*"};
scm scm_unspecified = {SCM, "*unspecified*"};
scm scm_closure = {SCM, "*closure*"};
scm scm_circular = {SCM, "*circular*"};
#if BOOT
scm scm_label = {
SCM, "label"};
#endif
scm scm_lambda = {SCM, "lambda"};
scm symbol_begin = {SCM, "begin"};
scm symbol_if = {SCM, "if"};
scm symbol_define = {SCM, "define"};
scm symbol_define_macro = {SCM, "define-macro"};
scm symbol_set_x = {SCM, "set!"};
scm symbol_quote = {SYMBOL, "quote"};
scm symbol_quasiquote = {SYMBOL, "quasiquote"};
scm symbol_unquote = {SYMBOL, "unquote"};
scm symbol_unquote_splicing = {SYMBOL, "unquote-splicing"};
scm symbol_sc_expand = {SYMBOL, "sc-expand"};
scm symbol_syntax = {SYMBOL, "syntax"};
scm symbol_quasisyntax = {SYMBOL, "quasisyntax"};
scm symbol_unsyntax = {SYMBOL, "unsyntax"};
scm symbol_unsyntax_splicing = {SYMBOL, "unsyntax-splicing"};
scm symbol_call_with_values = {SYMBOL, "call-with-values"};
scm symbol_current_module = {SYMBOL, "current-module"};
scm char_nul = {CHAR, .name="nul", .value=0};
scm char_backspace = {CHAR, .name="backspace", .value=8};
scm char_tab = {CHAR, .name="tab", .value=9};
scm char_newline = {CHAR, .name="newline", .value=10};
scm char_vt = {CHAR, .name="vt", .value=11};
scm char_page = {CHAR, .name="page", .value=12};
scm char_return = {CHAR, .name="return", .value=13};
scm char_space = {CHAR, .name="space", .value=32};
// PRIMITIVES
#define ATOM_P(x) (x->type == PAIR ? &scm_f : &scm_t)
scm *
atom_p (scm *x)
{
return ATOM_P(x);
}
scm *
car (scm *x)
{
assert (x->type == PAIR);
return x->car;
}
scm *
cdr (scm *x)
{
assert (x->type == PAIR);
return x->cdr;
}
scm *
cons (scm *x, scm *y)
{
scm *p = (scm*)malloc (sizeof (scm));
p->type = PAIR;
p->car = x;
p->cdr = y;
return p;
}
#define EQ_P(x, y)\
((x == y \
|| (x->type == CHAR && y->type == CHAR \
&& x->value == y->value) \
|| (x->type == NUMBER && y->type == NUMBER \
&& x->value == y->value)) \
? &scm_t : &scm_f)
scm *
eq_p (scm *x, scm *y)
{
return EQ_P (x, y);
}
scm *
macro_p (scm *x)
{
return x->type == MACRO ? &scm_t : &scm_f;
}
scm *
null_p (scm *x)
{
return x == &scm_nil ? &scm_t : &scm_f;
}
#define PAIR_P(x) (x->type == PAIR ? &scm_t : &scm_f)
scm *
pair_p (scm *x)
{
return PAIR_P(x);
}
scm *
set_car_x (scm *x, scm *e)
{
assert (x->type == PAIR);
x->car = e;
return &scm_unspecified;
}
scm *
set_cdr_x (scm *x, scm *e)
{
assert (x->type == PAIR);
cache_invalidate (x->cdr);
x->cdr = e;
return &scm_unspecified;
}
scm *
set_env_x (scm *x, scm *e, scm *a)
{
cache_invalidate (x);
return set_cdr_x (assq (x, a), e);
}
scm *
quote (scm *x)
{
return cons (&symbol_quote, x);
}
scm *
quasiquote (scm *x)
{
return cons (&symbol_quasiquote, x);
}
#if BUILTIN_QUASIQUOTE
scm *
unquote (scm *x) //int must not add to environment
{
return cons (&symbol_unquote, x);
}
scm *unquote (scm *x);
scm scm_unquote = {FUNCTION1, .name="unquote", .function1=&unquote};
scm *
unquote_splicing (scm *x) //int must not add to environment
{
return cons (&symbol_unquote_splicing, x);
}
scm *unquote_splicing (scm *x);
scm scm_unquote_splicing = {FUNCTION1, .name="unquote-splicing", .function1=&unquote_splicing};
#endif // BUILTIN_QUASIQUOTE
scm *
syntax (scm *x)
{
return cons (&symbol_syntax, x);
}
scm *
quasisyntax (scm *x)
{
return cons (&symbol_quasisyntax, x);
}
scm *
unsyntax (scm *x) //int must not add to environment
{
return cons (&symbol_unsyntax, x);
}
scm *unsyntax (scm *x);
scm scm_unsyntax = {FUNCTION1, .name="unsyntax", .function1=&unsyntax};
scm *
unsyntax_splicing (scm *x) //int must not add to environment
{
return cons (&symbol_unsyntax_splicing, x);
}
scm *unsyntax_splicing (scm *x);
scm scm_unsyntax_splicing = {FUNCTION1, .name="unsyntax-splicing", .function1=&unsyntax_splicing};
//Library functions
// Derived, non-primitives
scm *caar (scm *x) {return car (car (x));}
scm *cadr (scm *x) {return car (cdr (x));}
scm *cdar (scm *x) {return cdr (car (x));}
scm *cddr (scm *x) {return cdr (cdr (x));}
scm *caaar (scm *x) {return car (car (car (x)));}
scm *caadr (scm *x) {return car (car (cdr (x)));}
scm *caddr (scm *x) {return car (cdr (cdr (x)));}
scm *cdadr (scm *x) {return cdr (car (cdr (x)));}
scm *cadar (scm *x) {return car (cdr (car (x)));}
scm *cddar (scm *x) {return cdr (cdr (car (x)));}
scm *cdddr (scm *x) {return cdr (cdr (cdr (x)));}
scm *
pairlis (scm *x, scm *y, scm *a)
{
if (x == &scm_nil)
return a;
if (atom_p (x) == &scm_t)
return cons (cons (x, y), a);
return cons (cons (car (x), car (y)),
pairlis (cdr (x), cdr (y), a));
}
scm *
assq (scm *x, scm *a)
{
while (a != &scm_nil && EQ_P (x, a->car->car) == &scm_f) a = a->cdr;
return a != &scm_nil ? a->car : &scm_f;
}
#define ENV_CACHE 1
#define CACHE_SIZE 50
#define ENV_HEAD 15
#if !ENV_CACHE
scm *
assq_ref_cache (scm *x, scm *a) //internal
{
x = assq (x, a);
if (x == &scm_f) return &scm_f;
return x->cdr;
}
scm*cache_invalidate (scm*x){}
scm*cache_invalidate_range (scm*p,scm*a){}
scm*cache_save (scm*p){}
scm*cache_lookup (scm*x){}
#else // ENV_CACHE
scm *env_cache_cars[CACHE_SIZE];
scm *env_cache_cdrs[CACHE_SIZE];
int cache_threshold = 0;
scm *
cache_save (scm *p)
{
int n = p->car->value;
if (n < cache_threshold) return &scm_unspecified;
int j = -1;
for (int i=0; i < CACHE_SIZE; i++) {
if (!env_cache_cars[i]) {
j = i;
break;
}
if (env_cache_cars[i] == p->car) return &scm_unspecified;
if (n > -1 * env_cache_cars[i]->value) {
n = env_cache_cars[i]->value * -1;
j = i;
}
}
if (j >= 0) {
cache_threshold = p->car->value * -1;
p->car->value *= -1;
if (env_cache_cars[j]) env_cache_cars[j]->value *= -1;
//fprintf (stderr, "caching: %s [%d]\n", p->car->name, p->car->value);
env_cache_cars[j] = p->car;
env_cache_cdrs[j] = p->cdr;
}
return &scm_unspecified;
}
scm *
cache_lookup (scm *x)
{
for (int i=0; i < CACHE_SIZE; i++) {
if (!env_cache_cars[i]) break;
if (env_cache_cars[i] == x) return env_cache_cdrs[i];
}
return &scm_undefined;
}
scm *
cache_invalidate (scm *x)
{
for (int i=0; i < CACHE_SIZE; i++) {
if (env_cache_cars[i] == x) {
x->value *= -1;
//fprintf (stderr, "dropping: %s [%d]\n", env_cache_cars[i]->name, env_cache_cars[i]->value);
env_cache_cars[i] = 0;
break;
}
}
return &scm_unspecified;
}
scm *
cache_invalidate_range (scm *p, scm *a)
{
do {
cache_invalidate (p->car->car);
p = p->cdr;
} while (p != a);
return &scm_unspecified;
}
scm *
assq_ref_cache (scm *x, scm *a)
{
x->value < 0 ? x->value-- : x->value++;
scm *c = cache_lookup (x);
if (c != &scm_undefined) return c;
int i = 0;
while (a != &scm_nil && x != a->car->car) {i++;a = a->cdr;}
if (a == &scm_nil) return &scm_undefined;
if (i>ENV_HEAD /* && a->car->value > cache_threshold*/) cache_save (a->car);
return a->car->cdr;
}
#endif // ENV_CACHE
scm *
evlis_env (scm *m, scm *a)
{
if (m == &scm_nil) return &scm_nil;
if (m->type != PAIR) return builtin_eval (m, a);
scm *e = builtin_eval (car (m), a);
return cons (e, evlis_env (cdr (m), a));
}
scm *
apply_env (scm *fn, scm *x, scm *a)
{
if (fn->type != PAIR)
{
if (fn == &scm_car) return x->car->car;
if (fn == &scm_cdr) return x->car->cdr;
if (builtin_p (fn) == &scm_t)
return call (fn, x);
if (eq_p (fn, &symbol_call_with_values) == &scm_t)
return call (&scm_call_with_values_env, append2 (x, cons (a, &scm_nil)));
if (fn == &symbol_current_module) return a;
}
else if (fn->car == &scm_lambda) {
scm *p = pairlis (cadr (fn), x, a);
cache_invalidate_range (p, a->cdr);
scm *r = builtin_eval (cons (&symbol_begin, cddr (fn)), cons (cons (&scm_closure, p), p));
cache_invalidate_range (p, a->cdr);
return r;
}
else if (fn->car == &scm_closure) {
scm *args = caddr (fn);
scm *body = cdddr (fn);
a = cdadr (fn);
a = cdr (a);
scm *p = pairlis (args, x, a);
cache_invalidate_range (p, a->cdr);
scm *r = builtin_eval (cons (&symbol_begin, body), cons (cons (&scm_closure, p), p));
cache_invalidate_range (p, a->cdr);
return r;
}
#if BOOT
else if (fn->car == &scm_label)
return apply_env (caddr (fn), x, cons (cons (cadr (fn), caddr (fn)), a));
#endif
scm *efn = builtin_eval (fn, a);
if (efn == &scm_f || efn == &scm_t) assert (!"apply bool");
if (efn->type == NUMBER) assert (!"apply number");
if (efn->type == STRING) assert (!"apply string");
return apply_env (efn, x, a);
}
scm *
builtin_eval (scm *e, scm *a)
{
if (builtin_p (e) == &scm_t) return e;
if (internal_p (e) == &scm_t) return e;
e = expand_macro_env (e, a);
if (e->type == SYMBOL) {
scm *y = assq_ref_cache (e, a);
if (y == &scm_undefined) {
fprintf (stderr, "eval: unbound variable: %s\n", e->name);
assert (!"unbound variable");
}
return y;
}
else if (e->type != PAIR)
return e;
else if (e->car->type != PAIR)
{
if (e->car == &symbol_quote)
return cadr (e);
if (e->car == &symbol_syntax)
return e;
if (e->car == &symbol_begin)
return begin (e, a);
if (e->car == &scm_lambda)
return make_closure (cadr (e), cddr (e), assq (&scm_closure, a));
if (e->car == &scm_closure)
return e;
if (e->car == &symbol_if)
return builtin_if (cdr (e), a);
#if !BOOT
if (e->car == &symbol_define)
return define (e, a);
if (e->car == &symbol_define_macro)
return define (e, a);
#else
if (e->car == &symbol_define) {
fprintf (stderr, "C DEFINE: %s\n", e->cdr->car->type == SYMBOL
? e->cdr->car->name
: e->cdr->car->car->name);
}
assert (e->car != &symbol_define);
assert (e->car != &symbol_define_macro);
#endif
if (e->car == &symbol_set_x)
return set_env_x (cadr (e), builtin_eval (caddr (e), a), a);
#if BUILTIN_QUASIQUOTE
if (e->car == &symbol_unquote)
return builtin_eval (cadr (e), a);
if (e->car == &symbol_quasiquote)
return eval_quasiquote (cadr (e), add_unquoters (a));
if (e->car == &symbol_unsyntax)
return builtin_eval (cadr (e), a);
if (e->car == &symbol_quasisyntax)
return eval_quasisyntax (cadr (e), add_unsyntaxers (a));
#endif //BUILTIN_QUASIQUOTE
}
return apply_env (e->car, evlis_env (e->cdr, a), a);
}
scm *
expand_macro_env (scm *e, scm *a)
{
scm *macro;
if (e->type == PAIR
&& (macro = lookup_macro (e->car, a)) != &scm_f)
return expand_macro_env (apply_env (macro, e->cdr, a), a);
return e;
}
scm *
begin (scm *e, scm *a)
{
scm *r = &scm_unspecified;
while (e != &scm_nil) {
r = builtin_eval (e->car, a);
e = e->cdr;
}
return r;
}
scm *
builtin_if (scm *e, scm *a)
{
if (builtin_eval (car (e), a) != &scm_f)
return builtin_eval (cadr (e), a);
if (cddr (e) != &scm_nil)
return builtin_eval (caddr (e), a);
return &scm_unspecified;
}
#if BUILTIN_QUASIQUOTE
scm *
eval_quasiquote (scm *e, scm *a)
{
if (e == &scm_nil) return e;
else if (atom_p (e) == &scm_t) return e;
else if (eq_p (car (e), &symbol_unquote) == &scm_t)
return builtin_eval (cadr (e), a);
else if (e->type == PAIR && e->car->type == PAIR
&& eq_p (caar (e), &symbol_unquote_splicing) == &scm_t)
return append2 (builtin_eval (cadar (e), a), eval_quasiquote (cdr (e), a));
return cons (eval_quasiquote (car (e), a), eval_quasiquote (cdr (e), a));
}
scm *
eval_quasisyntax (scm *e, scm *a)
{
if (e == &scm_nil) return e;
else if (atom_p (e) == &scm_t) return e;
else if (eq_p (car (e), &symbol_unsyntax) == &scm_t)
return builtin_eval (cadr (e), a);
else if (e->type == PAIR && e->car->type == PAIR
&& eq_p (caar (e), &symbol_unsyntax_splicing) == &scm_t)
return append2 (builtin_eval (cadar (e), a), eval_quasisyntax (cdr (e), a));
return cons (eval_quasisyntax (car (e), a), eval_quasisyntax (cdr (e), a));
}
#else
scm*add_unquoters (scm *a){}
scm*add_unsyntaxers (scm *a){}
scm*eval_unsyntax (scm *e, scm *a){}
scm*eval_quasiquote (scm *e, scm *a){}
scm*eval_quasisyntax (scm *e, scm *a){}
#endif // BUILTIN_QUASIQUOTE
//Helpers
scm *
builtin_p (scm *x)
{
return (x->type == FUNCTION0
|| x->type == FUNCTION1
|| x->type == FUNCTION2
|| x->type == FUNCTION3
|| x->type == FUNCTIONn)
? &scm_t : &scm_f;
}
scm *
boolean_p (scm *x)
{
return (x == &scm_t || x == &scm_f) ? &scm_t : &scm_f;
}
scm *
char_p (scm *x)
{
return x->type == CHAR ? &scm_t : &scm_f;
}
scm *
number_p (scm *x)
{
return x->type == NUMBER ? &scm_t : &scm_f;
}
scm *
string_p (scm *x)
{
return x->type == STRING ? &scm_t : &scm_f;
}
scm *
internal_p (scm *x)
{
return x->type == SCM ? &scm_t : &scm_f;
}
scm *
symbol_p (scm *x)
{
return x->type == SYMBOL ? &scm_t : &scm_f;
}
scm *
vector_p (scm *x)
{
return x->type == VECTOR ? &scm_t : &scm_f;
}
scm *
display (scm *x/*...*/)
{
scm *e = car (x);
scm *p = cdr (x);
int fd = 1;
if (p->type == PAIR && p->car->type == NUMBER) fd = p->car->value;
FILE *f = fd == 1 ? stdout : stderr;
return display_helper (f, e, false, "", false);
}
scm *
display_ (FILE* f, scm *x) //internal
{
return display_helper (f, x, false, "", false);
}
scm *
call (scm *fn, scm *x)
{
if (fn->type == FUNCTION0)
return fn->function0 ();
if (x->car->type == VALUES)
x = cons (x->car->cdr->car, &scm_nil);
if (fn->type == FUNCTION1)
return fn->function1 (car (x));
if (fn->type == FUNCTION2)
return fn->function2 (car (x), cadr (x));
if (fn->type == FUNCTION3)
return fn->function3 (car (x), cadr (x), caddr (x));
if (fn->type == FUNCTIONn)
return fn->functionn (x);
return &scm_unspecified;
}
scm *
append2 (scm *x, scm *y)
{
if (x == &scm_nil) return y;
assert (x->type == PAIR);
return cons (car (x), append2 (cdr (x), y));
}
scm *
append (scm *x/*...*/)
{
if (x == &scm_nil) return &scm_nil;
return append2 (car (x), append (cdr (x)));
}
scm *
make_char (int x)
{
scm *p = (scm*)malloc (sizeof (scm));
p->type = CHAR;
p->value = x;
return p;
}
scm *
make_macro (scm *name, scm *x)
{
scm *p = (scm*)malloc (sizeof (scm));
p->type = MACRO;
p->macro = x;
p->name = name->name;
return p;
}
scm *
make_number (int x)
{
scm *p = (scm*)malloc (sizeof (scm));
p->type = NUMBER;
p->value = x;
return p;
}
scm *
make_string (char const *s)
{
scm *p = (scm*)malloc (sizeof (scm));
p->type = STRING;
p->name = strdup (s);
return p;
}
scm *symbols = 0;
scm *
internal_lookup_symbol (char const *s)
{
scm *x = symbols;
while (x && strcmp (s, x->car->name)) x = x->cdr;
if (x) x = x->car;
return x;
}
scm *
internal_make_symbol (char const *s)
{
scm *x = (scm*)malloc (sizeof (scm));
x->type = SYMBOL;
x->name = strdup (s);
x->value = 0;
symbols = cons (x, symbols);
return x;
}
scm *
make_symbol (char const *s)
{
scm *x = internal_lookup_symbol (s);
return x ? x : internal_make_symbol (s);
}
scm *
make_vector (scm *n)
{
scm *p = (scm*)malloc (sizeof (scm));
p->type = VECTOR;
p->length = n->value;
p->vector = (scm**)malloc (n->value * sizeof (scm*));
for (int i=0; i<n->value; i++) p->vector[i] = &scm_unspecified;
return p;
}
scm *
string (scm *x/*...*/)
{
char buf[STRING_MAX] = "";
char *p = buf;
while (x != &scm_nil)
{
scm *s = car (x);
assert (s->type == CHAR);
*p++ = s->value;
x = cdr (x);
}
return make_string (buf);
}
scm *
string_append (scm *x/*...*/)
{
char buf[STRING_MAX] = "";
while (x != &scm_nil)
{
scm *s = car (x);
assert (s->type == STRING);
strcat (buf, s->name);
x = cdr (x);
}
return make_string (buf);
}
scm *
list_to_string (scm *x)
{
char buf[STRING_MAX] = "";
char *p = buf;
while (x != &scm_nil)
{
scm *s = car (x);
assert (s->type == CHAR);
*p++ = s->value;
x = cdr (x);
}
*p = 0;
return make_string (buf);
}
scm *
string_length (scm *x)
{
assert (x->type == STRING);
return make_number (strlen (x->name));
}
scm *
string_ref (scm *x, scm *k)
{
assert (x->type == STRING);
assert (k->type == NUMBER);
return make_char (x->name[k->value]);
}
scm *
substring (scm *x/*...*/)
{
assert (x->type == PAIR);
assert (x->car->type == STRING);
char const *s = x->car->name;
assert (x->cdr->car->type == NUMBER);
int start = x->cdr->car->value;
int end = strlen (s);
if (x->cdr->cdr->type == PAIR) {
assert (x->cdr->cdr->car->type == NUMBER);
assert (x->cdr->cdr->car->value <= end);
end = x->cdr->cdr->car->value;
}
char buf[STRING_MAX];
strncpy (buf, s+start, end - start);
buf[end-start] = 0;
return make_string (buf);
}
scm *
length (scm *x)
{
int n = 0;
while (x != &scm_nil)
{
n++;
x = cdr (x);
}
return make_number (n);
}
scm *
last_pair (scm *x)
{
//if (x != &scm_nil && cdr (x) != &scm_nil)
//return last_pair (cdr (x));
while (x != &scm_nil && cdr (x) != &scm_nil)
x = cdr (x);
return x;
}
scm *
builtin_list (scm *x/*...*/)
{
return x;
}
scm *
values (scm *x/*...*/)
{
scm *v = cons (0, x);
v->type = VALUES;
return v;
}
scm *
call_with_values_env (scm *producer, scm *consumer, scm *a)
{
scm *v = apply_env (producer, &scm_nil, a);
if (v->type == VALUES)
v = v->cdr;
return apply_env (consumer, v, a);
}
scm *
vector_length (scm *x)
{
assert (x->type == VECTOR);
return make_number (x->length);
}
scm *
vector_ref (scm *x, scm *i)
{
assert (x->type == VECTOR);
assert (i->value < x->length);
return x->vector[i->value];
}
scm *
vector_set_x (scm *x, scm *i, scm *e)
{
assert (x->type == VECTOR);
assert (i->value < x->length);
x->vector[i->value] = e;
return &scm_unspecified;
}
scm *
lookup (char const *s, scm *a)
{
if (isdigit (*s) || (*s == '-' && isdigit (*(s+1))))
return make_number (atoi (s));
scm *x;
x = internal_lookup_symbol (s);
if (x) return x;
if (*s == '\'') return &symbol_quote;
if (*s == '`') return &symbol_quasiquote;
if (*s == ',' && *(s+1) == '@') return &symbol_unquote_splicing;
if (*s == ',') return &symbol_unquote;
if (*s == '#' && *(s+1) == '\'') return &symbol_syntax;
if (*s == '#' && *(s+1) == '`') return &symbol_quasisyntax;
if (*s == '#' && *(s+1) == ',' && *(s+2) == '@') return &symbol_unsyntax_splicing;
if (*s == '#' && *(s+1) == ',') return &symbol_unsyntax;
if (!strcmp (s, "EOF")) {
fprintf (stderr, "mes: got EOF\n");
return &scm_nil; // `EOF': eval program, which may read stdin
}
return internal_make_symbol (s);
}
scm *
lookup_char (int c, scm *a)
{
char buf[2];
buf[0] = c;
buf[1] = 0;
return lookup (buf, a);
}
char const *
list2str (scm *l) // char*
{
static char buf[STRING_MAX];
char *p = buf;
while (l != &scm_nil) {
scm *c = car (l);
assert (c->type == NUMBER);
*p++ = c->value;
l = cdr (l);
}
*p = 0;
return buf;
}
scm*
list_to_vector (scm *x)
{
temp_number.value = length (x)->value;
scm *v = make_vector (&temp_number);
scm **p = v->vector;
while (x != &scm_nil)
{
*p++ = car (x);
x = cdr (x);
}
return v;
}
scm*
integer_to_char (scm *x)
{
assert (x->type == NUMBER);
return make_char (x->value);
}
scm*
char_to_integer (scm *x)
{
assert (x->type == CHAR);
return make_number (x->value);
}
scm*
number_to_string (scm *x)
{
assert (x->type == NUMBER);
char buf[STRING_MAX];
sprintf (buf,"%d", x->value);
return make_string (buf);
}
scm*
builtin_exit (scm *x)
{
assert (x->type == NUMBER);
exit (x->value);
}
scm*
string_to_symbol (scm *x)
{
assert (x->type == STRING);
return make_symbol (x->name);
}
scm*
symbol_to_string (scm *x)
{
assert (x->type == SYMBOL);
return make_string (x->name);
}
scm*
vector_to_list (scm *v)
{
scm *x = &scm_nil;
for (int i = 0; i < v->length; i++)
x = append2 (x, cons (v->vector[i], &scm_nil));
return x;
}
scm *
newline (scm *p/*...*/)
{
int fd = 1;
if (p->type == PAIR && p->car->type == NUMBER) fd = p->car->value;
FILE *f = fd == 1 ? stdout : stderr;
fputs ("\n", f);
return &scm_unspecified;
}
scm *
force_output (scm *p/*...*/)
{
int fd = 1;
if (p->type == PAIR && p->car->type == NUMBER) fd = p->car->value;
FILE *f = fd == 1 ? stdout : stderr;
fflush (f);
}
scm *
display_helper (FILE* f, scm *x, bool cont, char const *sep, bool quote)
{
scm *r;
fprintf (f, "%s", sep);
if (x->type == CHAR && x->value == char_nul.value) fprintf (f, "#\\%s", char_nul.name);
else if (x->type == CHAR && x->value == char_backspace.value) fprintf (f, "#\\%s", char_backspace.name);
else if (x->type == CHAR && x->value == char_tab.value) fprintf (f, "#\\%s", char_tab.name);
else if (x->type == CHAR && x->value == char_newline.value) fprintf (f, "#\\%s", char_newline.name);
else if (x->type == CHAR && x->value == char_vt.value) fprintf (f, "#\\%s", char_vt.name);
else if (x->type == CHAR && x->value == char_page.value) fprintf (f, "#\\%s", char_page.name);
else if (x->type == CHAR && x->value == char_return.value) fprintf (f, "#\\%s", char_return.name);
else if (x->type == CHAR && x->value == char_space.value) fprintf (f, "#\\%s", char_space.name);
else if (x->type == CHAR) fprintf (f, "#\\%c", x->value);
else if (x->type == MACRO) {
fprintf (f, "(*macro* ");
display_helper (f, x->macro, cont, sep, quote);
fprintf (f, ")");
}
else if (x->type == NUMBER) fprintf (f, "%d", x->value);
else if (x->type == PAIR) {
if (car (x) == &scm_circular) {
fprintf (f, "(*circ* . #-1#)");
return &scm_unspecified;
}
if (car (x) == &scm_closure) {
fprintf (f, "(*closure* . #-1#)");
return &scm_unspecified;
}
if (car (x) == &scm_quote) {
fprintf (f, "'");
return display_helper (f, car (cdr (x)), cont, "", true);
}
if (!cont) fprintf (f, "(");
display_ (f, car (x));
if (cdr (x)->type == PAIR)
display_helper (f, cdr (x), true, " ", false);
else if (cdr (x) != &scm_nil) {
fprintf (f, " . ");
display_ (f, cdr (x));
}
if (!cont) fprintf (f, ")");
}
else if (x->type == VECTOR) {
fprintf (f, "#(", x->length);
for (int i = 0; i < x->length; i++) {
if (x->vector[i]->type == VECTOR)
fprintf (f, "%s#(...)", i ? " " : "");
else
display_helper (f, x->vector[i], false, i ? " " : "", false);
}
fprintf (f, ")");
}
else if (builtin_p (x) == &scm_t) fprintf (f, "#<procedure %s>", x->name);
else if (atom_p (x) == &scm_t) fprintf (f, "%s", x->name);
return &scm_unspecified;
}
// READ
int
ungetchar (int c) //int
{
return ungetc (c, stdin);
}
int
peekchar () //int
{
int c = getchar ();
ungetchar (c);
return c;
}
scm*
peek_char ()
{
return make_char (peekchar ());
}
scm *
read_char ()
{
return make_char (getchar ());
}
scm *
write_char (scm *x/*...*/)
{
scm *c = car (x);
scm *p = cdr (x);
int fd = 1;
if (p->type == PAIR && p->car->type == NUMBER) fd = p->car->value;
FILE *f = fd == 1 ? stdout : stderr;
assert (c->type == NUMBER || c->type == CHAR);
fputc (c->value, f);
return c;
}
scm*
unget_char (scm *c)
{
assert (c->type == NUMBER || c->type == CHAR);
ungetchar (c->value);
return c;
}
int
readcomment (int c)
{
if (c == '\n') return c;
return readcomment (getchar ());
}
int
readblock (int c)
{
if (c == '!' && peekchar () == '#') return getchar ();
return readblock (getchar ());
}
scm *
readword (int c, char *w, scm *a)
{
if (c == EOF && !w) return &scm_nil;
if (c == '\n' && !w) return readword (getchar (), w, a);
if (c == '\n' && *w == '.' && w[1] == 0) return &scm_dot;
if (c == EOF || c == '\n') return lookup (w, a);
if (c == ' ') return readword ('\n', w, a);
if (c == '"' && !w) return readstring ();
if (c == '"') {ungetchar (c); return lookup (w, a);}
if (c == '(' && !w) return readlist (a);
if (c == '(') {ungetchar (c); return lookup (w, a);}
if (c == ')' && !w) {ungetchar (c); return &scm_nil;}
if (c == ')') {ungetchar (c); return lookup (w, a);}
if (c == ',' && peekchar () == '@') {getchar (); return cons (lookup (",@", a),
cons (readword (getchar (), w, a),
&scm_nil));}
if ((c == '\''
|| c == '`'
|| c == ',')
&& !w) {return cons (lookup_char (c, a),
cons (readword (getchar (), w, a),
&scm_nil));}
if (c == '#' && peekchar () == ',' && !w) {
getchar ();
if (peekchar () == '@'){getchar (); return cons (lookup ("#,@", a),
cons (readword (getchar (), w, a),
&scm_nil));}
return cons (lookup ("#,", a), cons (readword (getchar (), w, a), &scm_nil));
}
if (c == '#'
&& (peekchar () == '\''
|| peekchar () == '`')
&& !w) {char buf[3] = "#"; buf[1] = getchar (); return cons (lookup (buf, a),
cons (readword (getchar (), w, a),
&scm_nil));}
if (c == ';') {readcomment (c); return readword ('\n', w, a);}
if (c == '#' && peekchar () == 'x') {getchar (); return read_hex ();}
if (c == '#' && peekchar () == '\\') {getchar (); return read_character ();}
if (c == '#' && !w && peekchar () == '(') {getchar (); return list_to_vector (readlist (a));}
if (c == '#' && peekchar () == '(') {ungetchar (c); return lookup (w, a);}
if (c == '#' && peekchar () == '!') {getchar (); readblock (getchar ()); return readword (getchar (), w, a);}
char buf[STRING_MAX] = {0};
char ch = c;
char *p = w ? w + strlen (w) : buf;
*p = ch;
*(p+1) = 0;
return readword (getchar (), w ? w : buf, a);
}
scm *
read_hex ()
{
int n = 0;
int c = peekchar ();
while ((c >= '0' && c <= '9')
|| (c >= 'A' && c <= 'F')
|| (c >= 'a' && c <= 'f')) {
n <<= 4;
if (c >= 'a') n += c - 'a' + 10;
else if (c >= 'A') n += c - 'A' + 10;
else n+= c - '0';
getchar ();
c = peekchar ();
}
return make_number (n);
}
scm *
read_character ()
{
int c = getchar ();
if (c >= '0' && c <= '7'
&& peekchar () >= '0' && peekchar () <= '7') {
c = c - '0';
while (peekchar () >= '0' && peekchar () <= '7') {
c <<= 3;
c += getchar () - '0';
}
}
else if (c >= 'a' && c <= 'z'
&& peekchar () >= 'a' && peekchar () <= 'z') {
char buf[STRING_MAX];
char *p = buf;
*p++ = c;
while (peekchar () >= 'a' && peekchar () <= 'z') {
*p++ = getchar ();
}
*p = 0;
if (!strcmp (buf, char_nul.name)) c = char_nul.value;
else if (!strcmp (buf, char_backspace.name)) c = char_backspace.value;
else if (!strcmp (buf, char_tab.name)) c = char_tab.value;
else if (!strcmp (buf, char_newline.name)) c = char_newline.value;
else if (!strcmp (buf, char_vt.name)) c = char_vt.value;
else if (!strcmp (buf, char_page.name)) c = char_page.value;
else if (!strcmp (buf, char_return.name)) c = char_return.value;
else if (!strcmp (buf, char_space.name)) c = char_space.value;
else {
fprintf (stderr, "char not supported: %s\n", buf);
assert (!"char not supported");
}
}
return make_char (c);
}
scm *
readstring ()
{
char buf[STRING_MAX];
char *p = buf;
int c = getchar ();
while (true) {
if (c == '"') break;
if (c == '\\' && peekchar () == '"') *p++ = getchar ();
else if (c == '\\' && peekchar () == 'n') {getchar (); *p++ = '\n';}
else if (c == EOF) assert (!"EOF in string");
else *p++ = c;
c = getchar ();
}
*p = 0;
return make_string (buf);
}
int
eat_whitespace (int c)
{
while (c == ' ' || c == '\t' || c == '\n') c = getchar ();
if (c == ';') return eat_whitespace (readcomment (c));
if (c == '#' && peekchar () == '!') {getchar (); readblock (getchar ()); return eat_whitespace (getchar ());}
return c;
}
scm *
readlist (scm *a)
{
int c = getchar ();
c = eat_whitespace (c);
if (c == ')') return &scm_nil;
scm *w = readword (c, 0, a);
if (w == &scm_dot)
return car (readlist (a));
return cons (w, readlist (a));
}
scm *
read_env (scm *a)
{
return readword (getchar (), 0, a);
}
scm *
greater_p (scm *x/*...*/)
{
int n = INT_MAX;
while (x != &scm_nil)
{
assert (x->car->type == NUMBER);
if (x->car->value >= n) return &scm_f;
n = x->car->value;
x = cdr (x);
}
return &scm_t;
}
scm *
less_p (scm *x/*...*/)
{
int n = INT_MIN;
while (x != &scm_nil)
{
assert (x->car->type == NUMBER);
if (x->car->value <= n) return &scm_f;
n = x->car->value;
x = cdr (x);
}
return &scm_t;
}
scm *
is_p (scm *x/*...*/)
{
if (x == &scm_nil) return &scm_t;
assert (x->car->type == NUMBER);
int n = x->car->value;
x = cdr (x);
while (x != &scm_nil)
{
if (x->car->value != n) return &scm_f;
x = cdr (x);
}
return &scm_t;
}
scm *
minus (scm *x/*...*/)
{
scm *a = car (x);
assert (a->type == NUMBER);
int n = a->value;
x = cdr (x);
if (x == &scm_nil)
n = -n;
while (x != &scm_nil)
{
assert (x->car->type == NUMBER);
n -= x->car->value;
x = cdr (x);
}
return make_number (n);
}
scm *
plus (scm *x/*...*/)
{
int n = 0;
while (x != &scm_nil)
{
assert (x->car->type == NUMBER);
n += x->car->value;
x = cdr (x);
}
return make_number (n);
}
scm *
divide (scm *x/*...*/)
{
int n = 1;
if (x != &scm_nil) {
assert (x->car->type == NUMBER);
n = x->car->value;
x = cdr (x);
}
while (x != &scm_nil)
{
assert (x->car->type == NUMBER);
n /= x->car->value;
x = cdr (x);
}
return make_number (n);
}
scm *
modulo (scm *a, scm *b)
{
assert (a->type == NUMBER);
assert (b->type == NUMBER);
return make_number (a->value % b->value);
}
scm *
multiply (scm *x/*...*/)
{
int n = 1;
while (x != &scm_nil)
{
assert (x->car->type == NUMBER);
n *= x->car->value;
x = cdr (x);
}
return make_number (n);
}
scm *
logior (scm *x/*...*/)
{
int n = 0;
while (x != &scm_nil)
{
assert (x->car->type == NUMBER);
n |= x->car->value;
x = cdr (x);
}
return make_number (n);
}
scm *add_environment (scm *a, char const *name, scm *x);
#if BUILTIN_QUASIQUOTE
scm *
add_unquoters (scm *a)
{
a = cons (cons (&symbol_unquote, &scm_unquote), a);
a = cons (cons (&symbol_unquote_splicing, &scm_unquote_splicing), a);
return a;
}
scm *
add_unsyntaxers (scm *a)
{
a = cons (cons (&symbol_unsyntax, &scm_unsyntax), a);
a = cons (cons (&symbol_unsyntax_splicing, &scm_unsyntax_splicing), a);
return a;
}
#endif // BUILTIN_QUASIQUOTE
scm *
add_environment (scm *a, char const *name, scm *x)
{
return cons (cons (make_symbol (name), x), a);
}
scm *
mes_environment ()
{
scm *a = &scm_nil;
#include "symbols.i"
#if BOOT
symbols = cons (&scm_label, symbols);
a = cons (cons (&scm_label, &scm_t), a);
#endif
a = cons (cons (&scm_f, &scm_f), a);
a = cons (cons (&scm_nil, &scm_nil), a);
a = cons (cons (&scm_t, &scm_t), a);
a = cons (cons (&scm_unspecified, &scm_unspecified), a);
a = cons (cons (&symbol_begin, &symbol_begin), a);
a = cons (cons (&symbol_quote, &scm_quote), a);
a = cons (cons (&symbol_syntax, &scm_syntax), a);
#if MES_FULL
#include "environment.i"
#else
a = add_environment (a, "display", &scm_display);
a = add_environment (a, "newline", &scm_newline);
#endif
a = cons (cons (&scm_closure, a), a);
return a;
}
scm *
make_lambda (scm *args, scm *body)
{
return cons (&scm_lambda, cons (args, body));
}
scm *
make_closure (scm *args, scm *body, scm *a)
{
return cons (&scm_closure, cons (cons (&scm_circular, a), cons (args, body)));
}
#if !BOOT
scm *
define (scm *x, scm *a)
{
scm *e;
scm *name = cadr (x);
if (name->type != PAIR)
e = builtin_eval (caddr (x), cons (cons (cadr (x), cadr (x)), a));
else {
name = car (name);
scm *p = pairlis (cadr (x), cadr (x), a);
e = builtin_eval (make_lambda (cdadr (x), cddr (x)), p);
}
if (eq_p (car (x), &symbol_define_macro) == &scm_t)
e = make_macro (name, e);
scm *entry = cons (name, e);
scm *aa = cons (entry, &scm_nil);
set_cdr_x (aa, cdr (a));
set_cdr_x (a, aa);
scm *cl = assq (&scm_closure, a);
set_cdr_x (cl, aa);
return entry;
}
#else // BOOT
scm*define (scm *x, scm *a){}
#endif
scm *
define_macro (scm *x, scm *a)
{
}
scm *
lookup_macro (scm *x, scm *a)
{
if (x->type != SYMBOL) return &scm_f;
scm *m = assq_ref_cache (x, a);
if (macro_p (m) == &scm_t) return m->macro;
return &scm_f;
}
scm *
read_file (scm *e, scm *a)
{
if (e == &scm_nil) return e;
#if DEBUG
scm *x = cons (e, read_file (read_env (a), a));
display_ (stderr, x);
#else
return cons (e, read_file (read_env (a), a));
#endif
}
int
main (int argc, char *argv[])
{
if (argc > 1 && !strcmp (argv[1], "--help")) return puts ("Usage: mes < FILE\n");
if (argc > 1 && !strcmp (argv[1], "--version")) return puts ("Mes 0.0\n");
scm *a = mes_environment ();
display_ (stderr, builtin_eval (cons (&symbol_begin, read_file (read_env (a), a)), a));
fputs ("", stderr);
return 0;
}