static void fput_loc(struct exec *loc, FILE *f);
static void type_err(struct parse_context *c,
char *fmt, struct exec *loc,
- struct type *t1, int rules, struct type *t2);
+ struct type *t1, enum val_rules rules, struct type *t2);
static void tok_err(struct parse_context *c, char *fmt, struct token *t);
###### core functions
static void type_err(struct parse_context *c,
char *fmt, struct exec *loc,
- struct type *t1, int rules, struct type *t2)
+ struct type *t1, enum val_rules rules, struct type *t2)
{
fprintf(stderr, "%s:", c->file_name);
fput_loc(loc, stderr);
which can be `NULL` signifying "unknown". A `prop_err` flag set is
passed by reference. It has `Efail` set when an error is found, and
`Eretry` when the type for some element is set via propagation. If
-any expression cannot be evaluated immediately, `Enoconst` is set.
+any expression cannot be evaluated a compile time, `Eruntime` is set.
If the expression can be copied, `Emaycopy` is set.
-If it remains unchanged at `0`, then no more propagation is needed.
+If `Erval` is set, then the value cannot be assigned to because it is
+a temporary result. If `Erval` is clear but `Econst` is set, then
+the value can only be assigned once, when the variable is declared.
###### ast
- enum val_rules {Rboolok = 1<<1, Rnoconstant = 1<<2};
- enum prop_err {Efail = 1<<0, Eretry = 1<<1, Enoconst = 1<<2,
- Emaycopy = 1<<3};
+ enum val_rules {Rboolok = 1<<0,};
+ enum prop_err {Efail = 1<<0, Eretry = 1<<1, Eruntime = 1<<2,
+ Emaycopy = 1<<3, Erval = 1<<4, Econst = 1<<5};
###### forward decls
static struct type *propagate_types(struct exec *prog, struct parse_context *c, enum prop_err *perr,
- struct type *type, int rules);
+ struct type *type, enum val_rules rules);
###### core functions
static struct type *__propagate_types(struct exec *prog, struct parse_context *c, enum prop_err *perr,
- struct type *type, int rules)
+ enum prop_err *perr_local,
+ struct type *type, enum val_rules rules)
{
struct type *t;
}
static struct type *propagate_types(struct exec *prog, struct parse_context *c, enum prop_err *perr,
- struct type *type, int rules)
+ struct type *type, enum val_rules rules)
{
int pre_err = c->parse_error;
- struct type *ret = __propagate_types(prog, c, perr, type, rules);
+ enum prop_err perr_local = 0;
+ struct type *ret = __propagate_types(prog, c, perr, &perr_local, type, rules);
+ *perr |= perr_local & (Efail | Eretry);
if (c->parse_error > pre_err)
*perr |= Efail;
return ret;
###### forward decls
static void free_value(struct type *type, struct value *v);
- static int type_compat(struct type *require, struct type *have, int rules);
+ static int type_compat(struct type *require, struct type *have, enum val_rules rules);
static void type_print(struct type *type, FILE *f);
static void val_init(struct type *type, struct value *v);
static void dup_value(struct type *type,
###### type functions
- int (*compat)(struct type *this, struct type *other);
+ int (*compat)(struct type *this, struct type *other, enum val_rules rules);
###### ast functions
- static int type_compat(struct type *require, struct type *have, int rules)
+ static int type_compat(struct type *require, struct type *have,
+ enum val_rules rules)
{
if ((rules & Rboolok) && have == Tbool)
return 1; // NOTEST
return 1;
if (require->compat)
- return require->compat(require, have);
+ return require->compat(require, have, rules);
return require == have;
}
if (!type_compat(type, val->vtype, rules))
type_err(c, "error: expected %1 found %2",
prog, type, rules, val->vtype);
+ *perr |= Erval;
return val->vtype;
}
if (!type_compat(type, Tlabel, rules))
type_err(c, "error: expected %1 found %2",
prog, type, rules, Tlabel);
+ *perr |= Erval;
return Tlabel;
}
###### interp exec cases
return Tnone; // NOTEST
}
v = v->merged;
- if (v->constant && (rules & Rnoconstant)) {
- type_err(c, "error: Cannot assign to a constant: %v",
- prog, NULL, 0, NULL);
- type_err(c, "info: name was defined as a constant here",
- v->where_decl, NULL, 0, NULL);
- return v->type;
- }
if (v->type == Tnone && v->where_decl == prog)
type_err(c, "error: variable used but not declared: %v",
prog, NULL, 0, NULL);
v->type, rules, NULL);
}
if (!v->global || v->frame_pos < 0)
- *perr |= Enoconst;
- if (!type)
- return v->type;
- return type;
+ *perr |= Eruntime;
+ if (v->constant)
+ *perr |= Econst;
+ return v->type;
}
###### interp exec cases
free(ptr);
}
- static int array_compat(struct type *require, struct type *have)
+ static int array_compat(struct type *require, struct type *have,
+ enum val_rules rules)
{
if (have->compat != require->compat)
return 0;
/* left must be an array, right must be a number,
* result is the member type of the array
*/
- propagate_types(b->right, c, perr, Tnum, 0);
- t = propagate_types(b->left, c, perr, NULL, rules & Rnoconstant);
+ propagate_types(b->right, c, perr_local, Tnum, 0);
+ t = propagate_types(b->left, c, perr, NULL, 0);
if (!t || t->compat != array_compat) {
type_err(c, "error: %1 cannot be indexed", prog, t, 0, NULL);
return NULL;
/* Nothing to do here */
}
- static int reference_compat(struct type *require, struct type *have)
+ static int reference_compat(struct type *require, struct type *have,
+ enum val_rules rules)
{
if (have->compat != require->compat)
return 0;
r->reftype = type;
*perr |= Eretry;
}
+ *perr |= Erval;
return type;
case RefNil:
if (type && type->free != reference_free)
r->reftype = type;
*perr |= Eretry;
}
+ *perr |= Erval;
return type;
case RefFree:
- t = propagate_types(r->right, c, perr, NULL, 0);
+ t = propagate_types(r->right, c, perr_local, NULL, 0);
if (t && t->free != reference_free)
type_err(c, "error: @free can only be assigned a reference, not %1",
prog, t, 0, NULL);
/* left must be a reference, and we return what it refers to */
/* FIXME how can I pass the expected type down? */
t = propagate_types(b->left, c, perr, NULL, 0);
+ *perr &= ~Erval;
if (!t || t->free != reference_free)
type_err(c, "error: Cannot dereference %1", b, t, 0, NULL);
else
val->function = NULL;
}
- static int function_compat(struct type *require, struct type *have)
+ static int function_compat(struct type *require, struct type *have,
+ enum val_rules rules)
{
// FIXME can I do anything here yet?
return 0;
prog, NULL, 0, NULL);
return NULL;
}
- *perr |= Enoconst;
- v->var->type->check_args(c, perr, v->var->type, args);
+ *perr |= Eruntime;
+ v->var->type->check_args(c, perr_local, v->var->type, args);
if (v->var->type->function.inline_result)
*perr |= Emaycopy;
+ *perr |= Erval;
return v->var->type->function.return_type;
}
struct binode *b2 = cast(binode, b->right);
struct type *t2;
- propagate_types(b->left, c, perr, Tbool, 0);
+ propagate_types(b->left, c, perr_local, Tbool, 0);
t = propagate_types(b2->left, c, perr, type, 0);
t2 = propagate_types(b2->right, c, perr, type ?: t, 0);
return t ?: t2;
if (type && type != Tbool)
type_err(c, "error: %1 operation found where %2 expected", prog,
Tbool, 0, type);
+ *perr |= Erval;
return Tbool;
###### interp binode cases
if (!type_compat(type, Tbool, 0))
type_err(c, "error: Comparison returns %1 but %2 expected", prog,
Tbool, rules, type);
+ *perr |= Erval;
return Tbool;
###### interp binode cases
if (!type_compat(type, Tnum, 0))
type_err(c, "error: Arithmetic returns %1 but %2 expected", prog,
Tnum, rules, type);
+ *perr |= Erval;
return Tnum;
case Concat:
if (!type_compat(type, Tstr, 0))
type_err(c, "error: Concat returns %1 but %2 expected", prog,
Tstr, rules, type);
+ *perr |= Erval;
return Tstr;
case StringConv:
type_err(c, // UNTESTED
"error: Can only convert string to number, not %1",
prog, type, 0, NULL);
+ *perr |= Erval;
return Tnum;
case Test:
if (!t || !t->test)
type_err(c, "error: '?' requires a testable value, not %1",
prog, t, 0, NULL);
+ *perr |= Erval;
return Tbool;
case Choose:
if (t && t->test == NULL)
type_err(c, "error: \"??\" requires a testable value, not %1",
prog, t, 0, NULL);
+ *perr |= Erval;
return t;
case Bracket:
- return propagate_types(b->right, c, perr, type, 0);
+ return propagate_types(b->right, c, perr, type, rules);
###### interp binode cases
else
b = cast(binode, b->right);
while (b) {
- propagate_types(b->left, c, perr, NULL, 0);
+ propagate_types(b->left, c, perr_local, NULL, 0);
b = cast(binode, b->right);
}
break;
* For Assign, left must not be constant.
* result is Tnone
*/
- t = propagate_types(b->left, c, perr, NULL,
- (b->op == Assign ? Rnoconstant : 0));
+ *perr &= ~(Erval | Econst);
+ t = propagate_types(b->left, c, perr, NULL, 0);
if (!b->right)
return Tnone;
if (t) {
- if (propagate_types(b->right, c, perr, t, 0) != t)
+ if (propagate_types(b->right, c, perr_local, t, 0) != t &&
+ *perr_local & Efail)
if (b->left->type == Xvar)
type_err(c, "info: variable '%v' was set as %1 here.",
cast(var, b->left)->var->where_set, t, rules, NULL);
} else {
- t = propagate_types(b->right, c, perr, NULL, 0);
+ t = propagate_types(b->right, c, perr_local, NULL, 0);
if (t)
- propagate_types(b->left, c, perr, t,
- (b->op == Assign ? Rnoconstant : 0));
+ propagate_types(b->left, c, perr, t, 0);
+ }
+ if (*perr & Erval)
+ type_err(c, "error: cannot assign to an rval", b,
+ NULL, 0, NULL);
+ else if (b->op == Assign && (*perr & Econst)) {
+ type_err(c, "error: Cannot assign to a constant: %v",
+ b->left, NULL, 0, NULL);
+ if (b->left->type == Xvar) {
+ struct var *var = cast(var, b->left);
+ struct variable *v = var->var;
+ type_err(c, "info: name was defined as a constant here",
+ v->where_decl, NULL, 0, NULL);
+ }
}
- if (t && t->dup == NULL && !(*perr & Emaycopy))
+ if (t && t->dup == NULL && !(*perr_local & Emaycopy))
type_err(c, "error: cannot assign value of type %1", b, t, 0, NULL);
return Tnone;
###### propagate binode cases
case Loop:
- t = propagate_types(b->right, c, perr, Tnone, 0);
+ t = propagate_types(b->right, c, perr_local, Tnone, 0);
if (!type_compat(Tnone, t, 0))
*perr |= Efail; // UNTESTED
return propagate_types(b->left, c, perr, type, rules);
} while (perr & Eretry);
if (perr & Efail)
c->parse_error += 1;
- else if (!(perr & Enoconst)) {
+ else if (!(perr & Eruntime)) {
progress = some;
struct value res = interp_exec(
c, vb->right, &v->var->type);
struct value fn = {.function = code};
struct type *t;
var_block_close(c, CloseFunction, code);
- t = add_anon_type(c, &function_prototype,
- "func %.*s", name->name->name.len,
+ t = add_anon_type(c, &function_prototype,
+ "func %.*s", name->name->name.len,
name->name->name.txt);
name->type = t;
t->function.params = reorder_bilist(args);
all_ok = 0;
if (!v->type->function.inline_result &&
!v->type->function.return_type->dup) {
- type_err(c, "error: function cannot return value of type %1",
+ type_err(c, "error: function cannot return value of type %1",
v->where_decl, v->type->function.return_type, 0, NULL);
}