expr visit_macro(expr const & e) {
buffer<expr> new_args;
for (unsigned i = 0; i < macro_num_args(e); i++)
new_args.push_back(visit(macro_arg(e, i)));
auto def = macro_def(e);
expr r = update_macro(e, new_args.size(), new_args.data());
if (def.trust_level() >= m_trust_lvl) {
if (optional<expr> new_r = m_tc.expand_macro(r)) {
return *new_r;
} else {
throw_generic_exception("failed to expand macro", e);
}
} else {
return r;
}
}
[[ noreturn ]] void throw_class_exception(expr const & m, pp_fn const & fn) { throw_generic_exception(m, fn); }
OBJECT_PTR eval_backquote(OBJECT_PTR form)
{
OBJECT_PTR car_obj;
assert(is_valid_object(form));
if(is_atom(form))
return form;
car_obj = car(form);
assert(is_valid_object(car_obj));
if(IS_SYMBOL_OBJECT(car_obj))
{
char buf[SYMBOL_STRING_SIZE];
print_symbol(car_obj, buf);
if(car_obj == COMMA)
{
OBJECT_PTR temp = compile(CADR(form), NIL);
#ifdef WIN32
if(temp == ERROR1)
#else
if(temp == ERROR)
#endif
{
throw_generic_exception("Backquote evaluation(1): compile failed");
return NIL;
}
reg_next_expression = cons(cons(FRAME, cons(cons(CONS_HALT_NIL, CADR(form)),
cons(temp, CADR(form)))),
CADR(form));
reg_current_value_rib = NIL;
while(car(reg_next_expression) != NIL)
{
//print_object(car(reg_next_expression));printf("\n");getchar();
eval(false);
if(in_error)
{
throw_generic_exception("Evaluation of backquote failed(1)");
return NIL;
}
}
reg_next_expression = cons(CONS_RETURN_NIL, cdr(reg_next_expression));
reg_current_value_rib = NIL;
return reg_accumulator;
}
}
if(form_contains_comma_at(form))
{
//1. loop through elements in form
//2. if element is not comma-at, call eval_backquote on
// it and append it to the result list without splicing
//3. if it is comma-at, get its symbol value and
// splice the value to the result list
//4. return the result list
OBJECT_PTR result = NIL;
OBJECT_PTR rest = form;
while(rest != NIL)
{
OBJECT_PTR ret;
OBJECT_PTR obj;
if(IS_CONS_OBJECT(car(rest)) &&
IS_SYMBOL_OBJECT(CAAR(rest)))
{
char buf[SYMBOL_STRING_SIZE];
print_symbol(CAAR(rest), buf);
if(CAAR(rest) == COMMA_AT)
{
OBJECT_PTR temp = compile(CADAR(rest), NIL);
#ifdef WIN32
if(temp == ERROR1)
#else
if(temp == ERROR)
#endif
{
throw_generic_exception("Backquote evaluation(2): compile failed");
return NIL;
}
reg_next_expression = cons(cons(FRAME, cons(cons(CONS_HALT_NIL, CADAR(rest)),
cons(temp, CADAR(rest)))),
CADAR(rest));
reg_current_value_rib = NIL;
while(car(reg_next_expression) != NIL)
{
eval(false);
if(in_error)
{
throw_generic_exception("Evaluation of backquote failed(2)");
return NIL;
}
}
reg_next_expression = cons(CONS_RETURN_NIL, cdr(reg_next_expression));
reg_current_value_rib = NIL;
obj = reg_accumulator;
if(result == NIL)
result = obj;
else
set_heap(last_cell(result) & POINTER_MASK, 1, obj);
}
else
{
obj = eval_backquote(car(rest));
if(result == NIL)
result = cons(obj, NIL);
else
set_heap(last_cell(result) & POINTER_MASK, 1, cons(obj, NIL));
}
}
else
{
obj = eval_backquote(car(rest));
if(result == NIL)
result = cons(obj, NIL);
else
set_heap(last_cell(result) & POINTER_MASK, 1, cons(obj, NIL));
}
rest = cdr(rest);
}
return result;
}
return cons(eval_backquote(car(form)),
eval_backquote(cdr(form)));
}
[[ noreturn ]] void throw_class_exception(char const * msg, expr const & m) { throw_generic_exception(msg, m); }