* General Public License for more details.
*/
+#define DBG_EVAL 0
#include "ao_lisp.h"
#include "ao_lisp_read.h"
c = lex_unget_c;
lex_unget_c = 0;
} else {
-#if AO_LISP_ALTOS
- static uint8_t at_eol;
-
- if (at_eol) {
- ao_cmd_readline();
- at_eol = 0;
- }
- c = ao_cmd_lex();
- if (c == '\n')
- at_eol = 1;
-#else
- c = getchar();
-#endif
+ c = ao_lisp_getc();
}
return c;
}
int count;
c = lex_get();
-// if (jumping)
-// return nil;
if (c == EOF)
return EOF;
c &= 0x7f;
count = 1;
while (count <= 3) {
c = lex_get();
-// if (jumping)
-// return nil;
if (c == EOF)
return EOF;
c &= 0x7f;
for (;;) {
c = lexc();
if (lex_class & ENDOFFILE)
- return AO_LISP_NIL;
+ return END;
-// if (jumping)
-// return nil;
if (lex_class & WHITE)
continue;
+ if (lex_class & COMMENT) {
+ while ((c = lexc()) != '\n') {
+ if (lex_class & ENDOFFILE)
+ return END;
+ }
+ continue;
+ }
+
if (lex_class & (BRA|KET|QUOTEC)) {
add_token(c);
end_token();
if (lex_class & STRINGC) {
for (;;) {
c = lexc();
-// if (jumping)
-// return nil;
if (lex_class & (STRINGC|ENDOFFILE)) {
end_token();
return STRING;
}
add_token (c);
c = lexc ();
-// if (jumping)
-// return nil;
if (lex_class & (NOTNAME)) {
// if (lex_class & ENDOFFILE)
// clearerr (f);
}
static int parse_token;
-static uint8_t been_here;
-static struct ao_lisp_cons *read_cons;
-static struct ao_lisp_cons *read_cons_tail;
-static struct ao_lisp_cons *read_stack;
-static ao_poly
-read_item(void)
+struct ao_lisp_cons *ao_lisp_read_cons;
+struct ao_lisp_cons *ao_lisp_read_cons_tail;
+struct ao_lisp_cons *ao_lisp_read_stack;
+
+static int
+push_read_stack(int cons, int in_quote)
+{
+ DBGI("push read stack %p %d\n", ao_lisp_read_cons, in_quote);
+ DBG_IN();
+ if (cons) {
+ ao_lisp_read_stack = ao_lisp_cons_cons(ao_lisp_cons_poly(ao_lisp_read_cons),
+ ao_lisp_cons_cons(ao_lisp_int_poly(in_quote),
+ ao_lisp_read_stack));
+ if (!ao_lisp_read_stack)
+ return 0;
+ }
+ ao_lisp_read_cons = NULL;
+ ao_lisp_read_cons_tail = NULL;
+ return 1;
+}
+
+static int
+pop_read_stack(int cons)
+{
+ int in_quote = 0;
+ if (cons) {
+ ao_lisp_read_cons = ao_lisp_poly_cons(ao_lisp_read_stack->car);
+ ao_lisp_read_stack = ao_lisp_poly_cons(ao_lisp_read_stack->cdr);
+ in_quote = ao_lisp_poly_int(ao_lisp_read_stack->car);
+ ao_lisp_read_stack = ao_lisp_poly_cons(ao_lisp_read_stack->cdr);
+ for (ao_lisp_read_cons_tail = ao_lisp_read_cons;
+ ao_lisp_read_cons_tail && ao_lisp_read_cons_tail->cdr;
+ ao_lisp_read_cons_tail = ao_lisp_poly_cons(ao_lisp_read_cons_tail->cdr))
+ ;
+ } else {
+ ao_lisp_read_cons = 0;
+ ao_lisp_read_cons_tail = 0;
+ ao_lisp_read_stack = 0;
+ }
+ DBG_OUT();
+ DBGI("pop read stack %p %d\n", ao_lisp_read_cons, in_quote);
+ return in_quote;
+}
+
+ao_poly
+ao_lisp_read(void)
{
struct ao_lisp_atom *atom;
char *string;
int cons;
+ int in_quote;
ao_poly v;
- if (!been_here) {
- ao_lisp_root_add(&ao_lisp_cons_type, &read_cons);
- ao_lisp_root_add(&ao_lisp_cons_type, &read_cons_tail);
- ao_lisp_root_add(&ao_lisp_cons_type, &read_stack);
- }
+ parse_token = lex();
+ DBGI("token %d (%s)\n", parse_token, token_string);
cons = 0;
- read_cons = read_cons_tail = read_stack = 0;
+ in_quote = 0;
+ ao_lisp_read_cons = ao_lisp_read_cons_tail = ao_lisp_read_stack = 0;
for (;;) {
while (parse_token == OPEN) {
- if (cons++)
- read_stack = ao_lisp_cons_cons(ao_lisp_cons_poly(read_cons), read_stack);
- read_cons = NULL;
- read_cons_tail = NULL;
+ if (!push_read_stack(cons, in_quote))
+ return AO_LISP_NIL;
+ cons++;
+ in_quote = 0;
parse_token = lex();
+ DBGI("token %d (%s)\n", parse_token, token_string);
}
switch (parse_token) {
- case ENDOFFILE:
+ case END:
default:
- v = AO_LISP_NIL;
+ if (cons)
+ ao_lisp_error(AO_LISP_EOF, "unexpected end of file");
+ return _ao_lisp_atom_eof;
break;
case NAME:
atom = ao_lisp_atom_intern(token_string);
else
v = AO_LISP_NIL;
break;
+ case QUOTE:
+ if (!push_read_stack(cons, in_quote))
+ return AO_LISP_NIL;
+ cons++;
+ in_quote = 1;
+ v = _ao_lisp_atom_quote;
+ break;
case CLOSE:
- if (cons)
- v = ao_lisp_cons_poly(read_cons);
- else
+ if (!cons) {
v = AO_LISP_NIL;
- if (--cons) {
- read_cons = ao_lisp_poly_cons(read_stack->car);
- read_stack = ao_lisp_poly_cons(read_stack->cdr);
- for (read_cons_tail = read_cons;
- read_cons_tail && read_cons_tail->cdr;
- read_cons_tail = ao_lisp_poly_cons(read_cons_tail->cdr))
- ;
+ break;
}
+ v = ao_lisp_cons_poly(ao_lisp_read_cons);
+ --cons;
+ in_quote = pop_read_stack(cons);
break;
}
- if (!cons)
- break;
+ /* loop over QUOTE ends */
+ for (;;) {
+ if (!cons)
+ return v;
+
+ struct ao_lisp_cons *read = ao_lisp_cons_cons(v, NULL);
+ if (!read)
+ return AO_LISP_NIL;
+
+ if (ao_lisp_read_cons_tail)
+ ao_lisp_read_cons_tail->cdr = ao_lisp_cons_poly(read);
+ else
+ ao_lisp_read_cons = read;
+ ao_lisp_read_cons_tail = read;
- struct ao_lisp_cons *read = ao_lisp_cons_cons(v, NULL);
- if (read_cons_tail)
- read_cons_tail->cdr = ao_lisp_cons_poly(read);
- else
- read_cons = read;
- read_cons_tail = read;
+ if (!in_quote || !ao_lisp_read_cons->cdr)
+ break;
+
+ v = ao_lisp_cons_poly(ao_lisp_read_cons);
+ --cons;
+ in_quote = pop_read_stack(cons);
+ }
parse_token = lex();
+ DBGI("token %d (%s)\n", parse_token, token_string);
}
return v;
}
-
-ao_poly
-ao_lisp_read(void)
-{
- parse_token = lex();
- return read_item();
-}