object *lookup_variable_value(object *var, object *env) {
object *frame;
object *vars;
object *vals;
if (debug)
{
fprintf(stderr, "entering lookup_variable_value searching for %s\n", var->data.symbol.value);
}
while (!is_the_empty_list(env)) {
frame = first_frame(env);
vars = frame_variables(frame);
vals = frame_values(frame);
if (debug)
{
fprintf(stderr, "1 searching symbol %s\n", var->data.symbol.value);
fprintf(stderr, "1 vars %p\n", vars);
}
while (!is_the_empty_list(vars)) {
if (is_pair(vars)) {
if (var == car(vars)) {
if (debug)
{
fprintf(stderr, "vals---\n");
write(stdout, is_pair(vals) ? car(vals) : the_empty_list);
fflush(stdout);
fprintf(stderr, "\nend---\n");
}
return is_pair(vals) ? car(vals) : the_empty_list;
}
}
else if(is_symbol(vars)) {
if (debug)
{
fprintf(stderr, "2 searched symbol %s\n", var->data.symbol.value);
fprintf(stderr, "last cdr symbol %s\n", vars->data.symbol.value);
}
if (var == vars) {
if (debug)
{
fprintf(stderr, "vals---\n");
write(stdout, vals);
fflush(stdout);
fprintf(stderr, "\nend---\n");
}
return vals;
}
else
{
break;
}
}
vars = cdr(vars);
vals = cdr(vals);
}
env = enclosing_environment(env);
}
fprintf(stderr, "unbound variable, %s\n", var->data.symbol.value);
exit(1);
}
void define_variable(item unev, item val, item env){
item frame = first_frame(env);
item vars, vals;
vars = frame_variables(frame);
vals = frame_value(frame);
while (1){
if (is_null(vars)){
add_binding_to_frame(unev, val, frame);
break;
}
else if (eq(unev, car(vars))){
set_car(vals, val);
break;
}
else{
vars = cdr(vars);
vals = cdr(vals);
}
}
}
void set_variable_value(item unev, item val, item env){
item vars, vals;
while (!eq(env, the_empty_environment())){
vars = frame_variables(first_frame(env));
vals = frame_value(first_frame(env));
while (1){
if (is_null(vars)){
env = enclosing_environment(env);
break;
}
else if (eq(unev, car(vars))){
set_car(vals, val);
}
else {
vars = cdr(vars);
vals = cdr(vals);
}
}
}
}
item lookup_variable_value(item exp, item env){
item vars, vals;
while (!eq(env, the_empty_environment())){
vars = frame_variables(first_frame(env));
vals = frame_value(first_frame(env));
while (1){
if (is_null(vars)){
env = enclosing_environment(env);
break;
}
else if (eq(exp, car(vars))){
return car(vals);
}
else {
vars = cdr(vars);
vals = cdr(vals);
}
}
}
fprintf(stderr, "Unbound variable");
exit(1);
}
void define_variable(object *var, object *val, object *env) {
object *frame;
object *vars;
object *vals;
object *prevals;
frame = first_frame(env);
vars = frame_variables(frame);
vals = frame_values(frame);
while (!is_the_empty_list(vars)) {
/* if (var == car(vars)) { */
/* set_car(vals, val); */
/* return; */
/* } */
if (is_pair(vars)) {
// printf("ispair\n");
if (var == car(vars)) {
if (debug)
{
printf("found match\n");
printf("\n---vals\n"); write(stdout, vals);
}
if (is_pair(vals))
{
set_car(vals, val);
return;
}
else
{
assert(0);
}
}
}
else if(is_symbol(vars)) {
if (debug)
{
printf("symbol\n");
fprintf(stderr, "2 searched symbol %s\n", var->data.symbol.value);
fprintf(stderr, "last cdr symbol %s\n", vars->data.symbol.value);
}
if (var == vars) {
if (debug)
{
printf("\n---vals\n"); write(stdout, vals);
printf("\n---prevals\n"); write(stdout, prevals);
}
// assert(0);
set_cdr(prevals, val);
// return vals;
return;
}
else
{
printf("\nx yes\n");
// assert(0);
break;
}
}
vars = cdr(vars);
prevals = vals;
vals = cdr(vals);
}
add_binding_to_frame(var, val, frame);
}
void set_variable_value(object *var, object *val, object *env) {
object *frame;
object *vars;
object *vals;
object *prevals;
while (!is_the_empty_list(env)) {
frame = first_frame(env);
vars = frame_variables(frame);
vals = frame_values(frame);
if (debug)
{
printf("\n---env\n"); write(stdout, env);
printf("\n---frame\n"); write(stdout, frame);
printf("\n---vars\n"); write(stdout, vars);
printf("\n---vals\n"); write(stdout, vals);
printf("\n---\n");
}
while (!is_the_empty_list(vars)) {
/* if (var == car(vars)) { */
/* set_car(vals, val); */
/* return; */
/* } */
if (is_pair(vars)) {
// printf("ispair\n");
if (var == car(vars)) {
if (debug)
{
printf("found match\n");
printf("\n---vals\n");
write(stdout, vals);
}
if (is_pair(vals))
{
set_car(vals, val);
return;
}
else /* TODO */
{
set_cdr(prevals, cons(val, the_empty_list));
return;
}
}
}
else if(is_symbol(vars)) {
if (debug)
{
printf("symbol\n");
fprintf(stderr, "2 searched symbol %s\n", var->data.symbol.value);
fprintf(stderr, "last cdr symbol %s\n", vars->data.symbol.value);
}
if (var == vars) {
if (debug)
{
printf("\n---vals\n"); write(stdout, vals);
printf("\n---prevals\n"); write(stdout, prevals);
}
// assert(0);
set_cdr(prevals, val);
// return vals;
return;
}
else
{
if (debug)
{
printf("\nx yes\n");
}
// assert(0);
break;
}
}
vars = cdr(vars);
prevals = vals;
vals = cdr(vals);
}
env = enclosing_environment(env);
}
fprintf(stderr, "unbound variable, %s\n", var->data.symbol.value);
exit(1);
}
