* 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
*/
-#define DBG_EVAL 0
#include "ao_lisp.h"
int
};
void
-ao_lisp_lambda_print(ao_poly poly)
+ao_lisp_lambda_write(ao_poly poly)
{
struct ao_lisp_lambda *lambda = ao_lisp_poly_lambda(poly);
struct ao_lisp_cons *cons = ao_lisp_poly_cons(lambda->code);
printf("%s", ao_lisp_args_name(lambda->args));
while (cons) {
printf(" ");
- ao_lisp_poly_print(cons->car);
+ ao_lisp_poly_write(cons->car);
cons = ao_lisp_poly_cons(cons->cdr);
}
printf(")");
ao_poly
ao_lisp_lambda_alloc(struct ao_lisp_cons *code, int args)
{
+ struct ao_lisp_lambda *lambda;
+ ao_poly formal;
+ struct ao_lisp_cons *cons;
+
+ formal = ao_lisp_arg(code, 0);
+ while (formal != AO_LISP_NIL) {
+ switch (ao_lisp_poly_type(formal)) {
+ case AO_LISP_CONS:
+ cons = ao_lisp_poly_cons(formal);
+ if (ao_lisp_poly_type(cons->car) != AO_LISP_ATOM)
+ return ao_lisp_error(AO_LISP_INVALID, "formal %p is not atom", cons->car);
+ formal = cons->cdr;
+ break;
+ case AO_LISP_ATOM:
+ formal = AO_LISP_NIL;
+ break;
+ default:
+ return ao_lisp_error(AO_LISP_INVALID, "formal %p is not atom", formal);
+ }
+ }
+
ao_lisp_cons_stash(0, code);
- struct ao_lisp_lambda *lambda = ao_lisp_alloc(sizeof (struct ao_lisp_lambda));
+ lambda = ao_lisp_alloc(sizeof (struct ao_lisp_lambda));
code = ao_lisp_cons_fetch(0);
- struct ao_lisp_cons *arg;
- int f;
-
if (!lambda)
return AO_LISP_NIL;
- if (!ao_lisp_check_argc(_ao_lisp_atom_lambda, code, 2, 2))
- return AO_LISP_NIL;
- if (!ao_lisp_check_argt(_ao_lisp_atom_lambda, code, 0, AO_LISP_CONS, 1))
- return AO_LISP_NIL;
- f = 0;
- arg = ao_lisp_poly_cons(ao_lisp_arg(code, 0));
- while (arg) {
- if (ao_lisp_poly_type(arg->car) != AO_LISP_ATOM)
- return ao_lisp_error(AO_LISP_INVALID, "formal %d is not an atom", f);
- arg = ao_lisp_poly_cons(arg->cdr);
- f++;
- }
-
lambda->type = AO_LISP_LAMBDA;
lambda->args = args;
lambda->code = ao_lisp_cons_poly(code);
- lambda->frame = ao_lisp_frame_poly(ao_lisp_frame_current);
+ lambda->frame = ao_lisp_frame_mark(ao_lisp_frame_current);
DBGI("build frame: "); DBG_POLY(lambda->frame); DBG("\n");
DBG_STACK();
return ao_lisp_lambda_poly(lambda);
}
ao_poly
-ao_lisp_lambda(struct ao_lisp_cons *cons)
+ao_lisp_do_lambda(struct ao_lisp_cons *cons)
{
return ao_lisp_lambda_alloc(cons, AO_LISP_FUNC_LAMBDA);
}
ao_poly
-ao_lisp_lexpr(struct ao_lisp_cons *cons)
-{
- return ao_lisp_lambda_alloc(cons, AO_LISP_FUNC_LEXPR);
-}
-
-ao_poly
-ao_lisp_nlambda(struct ao_lisp_cons *cons)
+ao_lisp_do_nlambda(struct ao_lisp_cons *cons)
{
return ao_lisp_lambda_alloc(cons, AO_LISP_FUNC_NLAMBDA);
}
ao_poly
-ao_lisp_macro(struct ao_lisp_cons *cons)
+ao_lisp_do_macro(struct ao_lisp_cons *cons)
{
return ao_lisp_lambda_alloc(cons, AO_LISP_FUNC_MACRO);
}
struct ao_lisp_lambda *lambda = ao_lisp_poly_lambda(ao_lisp_v);
struct ao_lisp_cons *cons = ao_lisp_poly_cons(ao_lisp_stack->values);
struct ao_lisp_cons *code = ao_lisp_poly_cons(lambda->code);
- struct ao_lisp_cons *args = ao_lisp_poly_cons(ao_lisp_arg(code, 0));
+ ao_poly formals;
struct ao_lisp_frame *next_frame;
int args_wanted;
+ ao_poly varargs = AO_LISP_NIL;
int args_provided;
+ int f;
+ struct ao_lisp_cons *vals;
DBGI("lambda "); DBG_POLY(ao_lisp_lambda_poly(lambda)); DBG("\n");
- args_wanted = ao_lisp_cons_length(args);
+ args_wanted = 0;
+ for (formals = ao_lisp_arg(code, 0);
+ ao_lisp_is_pair(formals);
+ formals = ao_lisp_poly_cons(formals)->cdr)
+ ++args_wanted;
+ if (formals != AO_LISP_NIL) {
+ if (ao_lisp_poly_type(formals) != AO_LISP_ATOM)
+ return ao_lisp_error(AO_LISP_INVALID, "bad lambda form");
+ varargs = formals;
+ }
/* Create a frame to hold the variables
*/
- if (lambda->args == AO_LISP_FUNC_LAMBDA)
- args_provided = ao_lisp_cons_length(cons) - 1;
- else
- args_provided = 1;
- if (args_wanted != args_provided)
- return ao_lisp_error(AO_LISP_INVALID, "need %d args, not %d", args_wanted, args_provided);
+ args_provided = ao_lisp_cons_length(cons) - 1;
+ if (varargs == AO_LISP_NIL) {
+ if (args_wanted != args_provided)
+ return ao_lisp_error(AO_LISP_INVALID, "need %d args, got %d", args_wanted, args_provided);
+ } else {
+ if (args_provided < args_wanted)
+ return ao_lisp_error(AO_LISP_INVALID, "need at least %d args, got %d", args_wanted, args_provided);
+ }
- next_frame = ao_lisp_frame_new(args_wanted);
+ ao_lisp_poly_stash(1, varargs);
+ next_frame = ao_lisp_frame_new(args_wanted + (varargs != AO_LISP_NIL));
+ varargs = ao_lisp_poly_fetch(1);
+ if (!next_frame)
+ return AO_LISP_NIL;
/* Re-fetch all of the values in case something moved */
lambda = ao_lisp_poly_lambda(ao_lisp_v);
cons = ao_lisp_poly_cons(ao_lisp_stack->values);
code = ao_lisp_poly_cons(lambda->code);
- args = ao_lisp_poly_cons(ao_lisp_arg(code, 0));
-
- switch (lambda->args) {
- case AO_LISP_FUNC_LAMBDA: {
- int f;
- struct ao_lisp_cons *vals = ao_lisp_poly_cons(cons->cdr);
-
- for (f = 0; f < args_wanted; f++) {
- DBGI("bind "); DBG_POLY(args->car); DBG(" = "); DBG_POLY(vals->car); DBG("\n");
- next_frame->vals[f].atom = args->car;
- next_frame->vals[f].val = vals->car;
- args = ao_lisp_poly_cons(args->cdr);
- vals = ao_lisp_poly_cons(vals->cdr);
- }
- break;
+ formals = ao_lisp_arg(code, 0);
+ vals = ao_lisp_poly_cons(cons->cdr);
+
+ next_frame->prev = lambda->frame;
+ ao_lisp_frame_current = next_frame;
+ ao_lisp_stack->frame = ao_lisp_frame_poly(ao_lisp_frame_current);
+
+ for (f = 0; f < args_wanted; f++) {
+ struct ao_lisp_cons *arg = ao_lisp_poly_cons(formals);
+ DBGI("bind "); DBG_POLY(arg->car); DBG(" = "); DBG_POLY(vals->car); DBG("\n");
+ ao_lisp_frame_bind(next_frame, f, arg->car, vals->car);
+ formals = arg->cdr;
+ vals = ao_lisp_poly_cons(vals->cdr);
}
- case AO_LISP_FUNC_LEXPR:
- case AO_LISP_FUNC_NLAMBDA:
- case AO_LISP_FUNC_MACRO:
- DBGI("bind "); DBG_POLY(args->car); DBG(" = "); DBG_POLY(cons->cdr); DBG("\n");
- next_frame->vals[0].atom = args->car;
- next_frame->vals[0].val = cons->cdr;
- break;
+ if (varargs) {
+ DBGI("bind "); DBG_POLY(varargs); DBG(" = "); DBG_POLY(ao_lisp_cons_poly(vals)); DBG("\n");
+ /*
+ * Bind the rest of the arguments to the final parameter
+ */
+ ao_lisp_frame_bind(next_frame, f, varargs, ao_lisp_cons_poly(vals));
+ } else {
+ /*
+ * Mark the cons cells from the actuals as freed for immediate re-use, unless
+ * the actuals point into the source function (nlambdas and macros), or if the
+ * stack containing them was copied as a part of a continuation
+ */
+ if (lambda->args == AO_LISP_FUNC_LAMBDA && !ao_lisp_stack_marked(ao_lisp_stack)) {
+ ao_lisp_stack->values = AO_LISP_NIL;
+ ao_lisp_cons_free(cons);
+ }
}
- next_frame->next = lambda->frame;
DBGI("eval frame: "); DBG_POLY(ao_lisp_frame_poly(next_frame)); DBG("\n");
- ao_lisp_frame_current = next_frame;
- ao_lisp_stack->frame = ao_lisp_frame_poly(ao_lisp_frame_current);
DBG_STACK();
- return ao_lisp_arg(code, 1);
+ DBGI("eval code: "); DBG_POLY(code->cdr); DBG("\n");
+ return code->cdr;
}
projects / fw / altos / blobdiff