/**
* dup an object
*/
lv_t *lisp_dup_item(lv_t *v) {
lv_t *r;
lv_t *vptr = v;
lv_t *rptr;
assert(v);
switch(v->type) {
case l_int:
r = lisp_create_int(0);
mpz_set(L_INT(r), L_INT(v));
return r;
case l_rational:
r = lisp_create_rational(1, 1);
mpq_set(L_RAT(r), L_RAT(v));
return r;
case l_float:
r = lisp_create_float(0.0);
mpfr_set(L_FLOAT(r), L_FLOAT(v), MPFR_ROUND_TYPE);
return r;
case l_bool:
return v;
case l_sym:
return lisp_create_symbol(L_SYM(v));
case l_str:
return lisp_create_string(L_STR(v));
case l_null:
return v;
case l_port:
/* can't really copy this -- it's a socket or a file
handle, or something else. */
return v;
case l_char:
return lisp_create_char(L_CHAR(v));
case l_fn:
/* can't really copy this either, but it's essentially
immutable */
return v;
case l_err:
return lisp_create_err(L_ERR(v));
case l_hash:
/* FIXME: should really be a copy */
return v;
case l_pair:
r = lisp_create_pair(NULL, NULL);
rptr = r;
while(vptr && L_CAR(vptr)) {
L_CAR(rptr) = lisp_dup_item(L_CAR(vptr));
vptr = L_CDR(vptr);
if(vptr) {
L_CDR(rptr) = lisp_create_pair(NULL, NULL);
rptr = L_CDR(rptr);
}
}
return r;
}
assert(0);
}
void repl(int level) {
char prompt[30];
char *cmd;
int quit = 0;
int line = 1;
lv_t *parsed_value;
lv_t *env_sym;
lv_t *result;
lv_t *arg;
lv_t *str;
char sym_buf[20];
lexec_t *exec;
exec = lisp_context_new(5); /* get r5rs environment */
while(!quit) {
snprintf(prompt, sizeof(prompt), "%d:%d> ", level, line);
// r!
cmd = readline(prompt);
if(!cmd) {
printf("\n");
quit = 1;
break;
}
if(!*cmd)
continue;
parsed_value = lisp_parse_string(cmd);
if(!parsed_value) {
fprintf(stderr, "synax error\n");
continue;
}
// e!
result = lisp_execute(exec, parsed_value);
// p!
if(result && !is_nil(result)) {
sprintf(sym_buf, "$%d", line);
env_sym = lisp_create_symbol(sym_buf);
c_hash_insert(L_CAR(exec->env), env_sym, result);
dprintf(1, "%s = ", sym_buf);
str = lisp_str_from_value(result);
printf("%s\n", L_STR(str));
}
// and l. ;)
add_history(cmd);
free(cmd);
line++;
}
}
/**
* generate a unique symbol. This should probably
*/
lv_t *p_gensym(lexec_t *exec, lv_t *v) {
static int sym_no=0;
char buffer[20];
assert(v && (v->type == l_pair || v->type == l_null));
rt_assert(c_list_length(v) == 0, le_arity, "gensym arity");
snprintf(buffer, sizeof(buffer), "<gensym-%05d>", sym_no++);
return lisp_create_symbol(buffer);
}
/**
* wrap a lisp value in a symbol (quote, dequote, etc)
*/
lv_t *lisp_wrap_type(char *symv, lv_t *v) {
lv_t *cdr = lisp_create_pair(v, NULL);
lv_t *car = lisp_create_pair(lisp_create_symbol(symv), cdr);
return car;
}
