static void push_function(struct thread *thread, int arg)
{
struct variable *var
= (struct variable *)COMPONENT(thread->component)->constant[arg];
obj_t value = var->value;
switch (var->function) {
case func_No:
type_error(value, obj_FunctionClass);
case func_Yes:
case func_Always:
break;
case func_Maybe:
if (instancep(value, obj_FunctionClass)) {
var->function = func_Yes;
break;
}
else if (value == obj_Unbound)
error("Unbound variable: %s", var->name);
else {
var->function = func_No;
type_error(value, obj_FunctionClass);
}
}
*thread->sp++ = value;
}
/* Look for an object with the given name in the named file and return a
callable "<c-function>" object for it. */
obj_t find_c_function(obj_t /* <string> */ symbol, obj_t lookup)
{
const char *string = string_chars(symbol);
struct symtab *syms;
int sym_count, i;
obj_t retval = obj_False;
if (lookup == obj_Unbound) {
if (mindy_dynamic_syms == NULL)
mindy_dynamic_syms = load_program_file();
return find_c_function(symbol, mindy_dynamic_syms);
} else if (lookup == obj_False)
return obj_False;
else if (!instancep(lookup, obj_ForeignFileClass)) {
error("Keyword file: is not a <foreign-file>: %=", lookup);
return retval; /* make lint happy */
} else if (instancep(lookup, obj_SharedFileClass)) {
shl_t *files = obj_ptr(struct shared_file *, lookup)->handles;
int file_count = obj_ptr(struct shared_file *, lookup)->file_count;
void *ptr;
for (i = 0; i < file_count; i++)
if (shl_findsym(&files[i], string, &ptr) == 0)
return(make_c_function(make_byte_string(string), ptr));
return retval;
} else {
obj_t check_type(obj_t thing, obj_t type)
{
if (!instancep(thing, type)) {
type_error(thing, type);
/* Never reached, but keeps the compiler happy. */
return 0;
}
else
return thing;
}
static void op_check_type(int byte, struct thread *thread)
{
obj_t *sp = thread->sp;
obj_t value = sp[-2];
obj_t type = sp[-1];
if (!instancep(value, type))
type_error(value, type);
thread->sp = sp - 1;
}
static void pop_value(struct thread *thread, int arg)
{
struct variable *var
= (struct variable *)COMPONENT(thread->component)->constant[arg];
obj_t value = *--thread->sp;
if (var->type != obj_False && !instancep(value, var->type))
type_error(value, var->type);
if (var->function != func_Always)
var->function = func_Maybe;
var->value = value;
}
static void op_check_type_function(int byte, struct thread *thread)
{
if (!instancep(thread->sp[-1], obj_FunctionClass))
type_error(thread->sp[-1], obj_FunctionClass);
}