void
free_task (struct task_s *task)
{
if ( task->refcnt )
return;
switch ( task->t )
{
case TASK_EVAL:
release_expression (task->d.task_eval_v.expr);
release_continuation (task->d.task_eval_v.cont);
break;
case TASK_APP1:
release_function (task->d.task_app1_v.erator);
release_expression (task->d.task_app1_v.rand);
release_continuation (task->d.task_app1_v.cont);
break;
case TASK_APP:
release_function (task->d.task_app_v.erator);
release_function (task->d.task_app_v.erand);
release_continuation (task->d.task_app_v.cont);
break;
case TASK_INVOKE:
release_continuation (task->d.task_invoke_v.cont);
release_function (task->d.task_invoke_v.val);
break;
default:
;
}
free (task);
}
// Parses a pair, assuming the opening left parenthesis has already been read.
static struct ParseResult parse_pair(const char *text) {
struct ParseResult result;
result.err_type = -1;
const char *s = text;
s += skip_whitespace(s);
if (*s == ')') {
s++;
result.expr = new_null();
goto chars_read;
}
struct ParseResult first = parse(s);
s += first.chars_read;
if (first.err_type != -1) {
result.err_type = first.err_type;
goto chars_read;
}
if (*s == '.') {
s++;
struct ParseResult second = parse(s);
s += second.chars_read;
if (second.err_type != -1) {
result.err_type = second.err_type;
release_expression(first.expr);
goto chars_read;
}
if (*s != ')') {
result.err_type = *s ? ERR_EXPECTED_RPAREN : ERR_UNEXPECTED_EOI;
release_expression(first.expr);
goto chars_read;
}
s++;
result.expr = new_pair(first.expr, second.expr);
} else {
struct ParseResult rest = parse_pair(s);
s += rest.chars_read;
if (rest.err_type != -1) {
result.err_type = rest.err_type;
release_expression(first.expr);
goto chars_read;
}
result.expr = new_pair(first.expr, rest.expr);
}
chars_read:
result.chars_read = (size_t)(s - text);
return result;
}
void
free_function (struct function_s *fun)
{
if ( fun->refcnt )
return;
switch ( fun->t )
{
case FUNCTION_K1:
release_function (fun->d.function_k1_v);
break;
case FUNCTION_S2:
release_function (fun->d.function_s2_v.x);
release_function (fun->d.function_s2_v.y);
break;
case FUNCTION_S1:
release_function (fun->d.function_s1_v);
break;
case FUNCTION_D1:
release_expression (fun->d.function_d1_v);
break;
case FUNCTION_CONT:
case FUNCTION_DCONT:
release_continuation (fun->d.function_cont_v);
break;
default:
;
}
free (fun);
}
void
free_expression (struct expression_s *expr)
{
if ( expr->refcnt )
return;
switch ( expr->t )
{
case EXPRESSION_FUNCTION:
release_function (expr->d.expression_function_v);
break;
case EXPRESSION_APPLICATION:
release_expression (expr->d.expression_application_v.rator);
release_expression (expr->d.expression_application_v.rand);
break;
}
free (expr);
}
void
free_continuation (struct continuation_s *cont)
{
if ( cont->refcnt )
return;
switch ( cont->t )
{
case CONTINUATION_APP1:
release_expression (cont->d.continuation_app1_v.rand);
release_continuation (cont->d.continuation_app1_v.cont);
break;
case CONTINUATION_APP:
release_function (cont->d.continuation_app_v.erator);
release_continuation (cont->d.continuation_app_v.cont);
break;
case CONTINUATION_DEL:
release_function (cont->d.continuation_del_v.erand);
release_continuation (cont->d.continuation_del_v.cont);
break;
default:
;
}
free (cont);
}