...

include/pocketpy/interpreter/vm.h

@@ -42,7 +42,6 @@ typedef struct pk_VM {
     pk_NameDict modules;
     c11_vector /*T=pk_TypeInfo*/ types;
 
-    py_TValue StopIteration;  // a special Exception class
     py_TValue builtins;       // builtins module
     py_TValue main;           // __main__ module
 
@@ -53,6 +52,7 @@ typedef struct pk_VM {
 
     py_TValue last_retval;
     bool has_error;
+    bool is_stopiteration;
     
     py_TValue reg[8];  // users' registers
 
@@ -91,6 +91,7 @@ py_Type pk_VM__new_type(pk_VM* self,
 pk_FrameResult pk_VM__vectorcall(pk_VM* self, uint16_t argc, uint16_t kwargc, bool opcall);
 
 const char* pk_opname(Opcode op);
+py_TValue* pk_arrayview(py_Ref self, int* size);
 
 // type registration
 void pk_object__register();
@@ -101,6 +102,8 @@ py_Type pk_bytes__register();
 py_Type pk_list__register();
 py_Type pk_function__register();
 py_Type pk_nativefunc__register();
+py_Type pk_range__register();
+py_Type pk_range_iterator__register();
 
 py_TValue pk_builtins__register();
 

include/pocketpy/pocketpy.h

@@ -244,13 +244,14 @@ void py_formatexc(char* out);
 #define TypeError(...) py_exception("TypeError", __VA_ARGS__)
 #define ValueError(...) py_exception("ValueError", __VA_ARGS__)
 #define IndexError(...) py_exception("IndexError", __VA_ARGS__)
-#define StopIteration() py_exception("StopIteration", "")
 #define NotImplementedError() py_exception("NotImplementedError", "")
 #define AttributeError(self, n)                                                                    \
     py_exception("AttributeError", "'%t' object has no attribute '%n'", (self)->type, (n))
 #define UnboundLocalError(n)                                                                       \
     py_exception("UnboundLocalError", "local variable '%n' referenced before assignment", (n))
 
+bool StopIteration();
+
 /************* Operators *************/
 /// Equivalent to `bool(val)`.
 /// Returns 1 if `val` is truthy, otherwise 0.
@@ -385,6 +386,7 @@ enum py_PredefinedTypes {
     tp_tuple,  // N slots
     tp_slice,  // 3 slots (start, stop, step)
     tp_range,
+    tp_range_iterator,
     tp_module,
     tp_function,
     tp_nativefunc,

src/interpreter/ceval.c

@@ -6,6 +6,7 @@
 #include <stdbool.h>
 
 static bool stack_binaryop(pk_VM* self, py_Name op, py_Name rop);
+static bool stack_unpack_sequence(pk_VM* self, uint16_t arg);
 
 #define DISPATCH()                                                                                 \
     do {                                                                                           \
@@ -32,7 +33,7 @@ static bool stack_binaryop(pk_VM* self, py_Name op, py_Name rop);
 #define STACK_SHRINK(n) (self->stack.sp -= n)
 #define PUSH(v)                                                                                    \
     do {                                                                                           \
-        *self->stack.sp = *v;                                                                      \
+        *self->stack.sp = *(v);                                                                    \
         self->stack.sp++;                                                                          \
     } while(0)
 #define POP() (--self->stack.sp)
@@ -693,6 +694,13 @@ pk_FrameResult pk_VM__run_top_frame(pk_VM* self) {
                 DISPATCH();
             }
 
+                //
+
+            case OP_UNPACK_SEQUENCE: {
+                if(!stack_unpack_sequence(self, byte.arg)) goto __ERROR;
+                DISPATCH();
+            }
+
             ///////////
             case OP_RAISE_ASSERT: {
                 if(byte.arg) {
@@ -756,3 +764,14 @@ bool py_binaryop(const py_Ref lhs, const py_Ref rhs, py_Name op, py_Name rop) {
     STACK_SHRINK(2);
     return ok;
 }
+
+static bool stack_unpack_sequence(pk_VM* self, uint16_t arg) {
+    int length;
+    py_TValue* p = pk_arrayview(TOP(), &length);
+    if(!p) return TypeError("expected list or tuple to unpack, got '%t'", TOP()->type);
+    if(length != arg) return ValueError("expected %d values to unpack, got %d", arg, length);
+    POP();
+    for(int i = 0; i < length; i++)
+        PUSH(p + i);
+    return true;
+}

src/interpreter/vm.c

@@ -62,7 +62,6 @@ void pk_VM__ctor(pk_VM* self) {
     pk_NameDict__ctor(&self->modules);
     c11_vector__ctor(&self->types, sizeof(pk_TypeInfo));
 
-    self->StopIteration = PY_NIL;
     self->builtins = PY_NIL;
     self->main = PY_NIL;
 
@@ -73,6 +72,7 @@ void pk_VM__ctor(pk_VM* self) {
 
     self->last_retval = PY_NIL;
     self->has_error = false;
+    self->is_stopiteration = false;
 
     self->__curr_class = PY_NIL;
     self->__dynamic_func_decl = NULL;
@@ -102,7 +102,8 @@ void pk_VM__ctor(pk_VM* self) {
     validate(tp_tuple, pk_VM__new_type(self, "tuple", tp_object, NULL, false));
 
     validate(tp_slice, pk_VM__new_type(self, "slice", tp_object, NULL, false));
-    validate(tp_range, pk_VM__new_type(self, "range", tp_object, NULL, false));
+    validate(tp_range, pk_range__register());
+    validate(tp_range_iterator, pk_range_iterator__register());
     validate(tp_module, pk_VM__new_type(self, "module", tp_object, NULL, false));
 
     validate(tp_function, pk_function__register());
@@ -130,7 +131,6 @@ void pk_VM__ctor(pk_VM* self) {
     validate(tp_stop_iteration, pk_VM__new_type(self, "StopIteration", tp_exception, NULL, false));
 #undef validate
 
-    self->StopIteration = *py_tpobject(tp_stop_iteration);
     self->builtins = pk_builtins__register();
 
     /* Setup Public Builtin Types */

src/public/modules.c

@@ -117,11 +117,8 @@ static bool _py_builtins__next(int argc, py_Ref argv) {
     PY_CHECK_ARGC(1);
     int res = py_next(argv);
     if(res == -1) return false;
-    if(res) {
-        return true;
-    } else {
-        return StopIteration();
-    }
+    if(res) return true;
+    return py_exception("StopIteration", "");
 }
 
 py_TValue pk_builtins__register() {

src/public/py_object.c

@@ -4,7 +4,7 @@
 
 static bool _py_object__new__(int argc, py_Ref argv) {
     assert(argc >= 1);
-    py_Type cls = argv[0].type;
+    py_Type cls = py_totype(py_arg(0));
     py_newobject(py_retval(), cls, 0, 0);
     return true;
 }
@@ -42,10 +42,24 @@ static bool _py_object__repr__(int argc, py_Ref argv) {
     return true;
 }
 
+static bool _py_type__repr__(int argc, py_Ref argv) {
+    PY_CHECK_ARGC(1);
+    c11_sbuf buf;
+    c11_sbuf__ctor(&buf);
+    pk_sprintf(&buf, "<class '%t'>", py_totype(argv));
+    c11_string* res = c11_sbuf__submit(&buf);
+    py_newstrn(py_retval(), res->data, res->size);
+    c11_string__delete(res);
+    return true;
+}
+
 void pk_object__register() {
     py_bindmagic(tp_object, __new__, _py_object__new__);
     py_bindmagic(tp_object, __hash__, _py_object__hash__);
     py_bindmagic(tp_object, __eq__, _py_object__eq__);
     py_bindmagic(tp_object, __ne__, _py_object__ne__);
     py_bindmagic(tp_object, __repr__, _py_object__repr__);
+
+    // type patch...
+    py_bindmagic(tp_type, __repr__, _py_type__repr__);
 }

src/public/py_ops.c

@@ -67,15 +67,13 @@ bool py_iter(const py_Ref val) {
 }
 
 int py_next(const py_Ref val) {
+    pk_VM* vm = pk_current_vm;
+    vm->is_stopiteration = false;
     py_Ref tmp = py_tpfindmagic(val->type, __next__);
     if(!tmp) return TypeError("'%t' object is not an iterator", val->type);
     bool ok = py_call(tmp, 1, val);
-    if(ok) {
-        py_Ref retval = py_retval();
-        bool is_end = retval->type == tp_type && py_totype(retval) == tp_stop_iteration;
-        return !is_end;
-    }
-    return -1;
+    if(ok) return true;
+    return vm->is_stopiteration ? 0 : -1;
 }
 
 int py_getattr(const py_Ref self, py_Name name, py_Ref out) { return -1; }

src/public/py_range.c

@@ -0,0 +1,99 @@
+#include "pocketpy/pocketpy.h"
+
+#include "pocketpy/common/utils.h"
+#include "pocketpy/objects/object.h"
+#include "pocketpy/interpreter/vm.h"
+
+typedef struct Range {
+    py_i64 start;
+    py_i64 stop;
+    py_i64 step;
+} Range;
+
+static bool _py_range__new__(int argc, py_Ref argv) {
+    Range* ud = py_newobject(py_retval(), tp_range, 0, sizeof(Range));
+    switch(argc - 1) {  // skip cls
+        case 1: {
+            PY_CHECK_ARG_TYPE(1, tp_int);
+            ud->start = 0;
+            ud->stop = py_toint(py_arg(1));
+            ud->step = 1;
+            break;
+        }
+        case 2:
+            PY_CHECK_ARG_TYPE(1, tp_int);
+            PY_CHECK_ARG_TYPE(2, tp_int);
+            ud->start = py_toint(py_arg(1));
+            ud->stop = py_toint(py_arg(2));
+            ud->step = 1;
+            break;
+        case 3:
+            PY_CHECK_ARG_TYPE(1, tp_int);
+            PY_CHECK_ARG_TYPE(2, tp_int);
+            PY_CHECK_ARG_TYPE(3, tp_int);
+            ud->start = py_toint(py_arg(1));
+            ud->stop = py_toint(py_arg(2));
+            ud->step = py_toint(py_arg(3));
+            break;
+        default: return TypeError("range() expected at most 3 arguments, got %d", argc - 1);
+    }
+    if(ud->step == 0) return ValueError("range() arg 3 must not be zero");
+    return true;
+}
+
+static bool _py_range__iter__(int argc, py_Ref argv) {
+    PY_CHECK_ARGC(1);
+    return py_tpcall(tp_range_iterator, 1, argv);
+}
+
+py_Type pk_range__register() {
+    pk_VM* vm = pk_current_vm;
+    py_Type type = pk_VM__new_type(vm, "range", tp_object, NULL, false);
+
+    py_bindmagic(type, __new__, _py_range__new__);
+    py_bindmagic(type, __iter__, _py_range__iter__);
+    return type;
+}
+
+typedef struct RangeIterator {
+    Range range;
+    py_i64 current;
+} RangeIterator;
+
+static bool _py_range_iterator__new__(int argc, py_Ref argv) {
+    PY_CHECK_ARGC(2);
+    PY_CHECK_ARG_TYPE(1, tp_range);
+    RangeIterator* ud = py_newobject(py_retval(), tp_range_iterator, 0, sizeof(RangeIterator));
+    ud->range = *(Range*)py_touserdata(py_arg(1));
+    ud->current = ud->range.start;
+    return true;
+}
+
+static bool _py_range_iterator__iter__(int argc, py_Ref argv) {
+    PY_CHECK_ARGC(1);
+    *py_retval() = *py_arg(0);
+    return true;
+}
+
+static bool _py_range_iterator__next__(int argc, py_Ref argv) {
+    PY_CHECK_ARGC(1);
+    RangeIterator* ud = py_touserdata(py_arg(0));
+    if(ud->range.step > 0) {
+        if(ud->current >= ud->range.stop) return StopIteration();
+    } else {
+        if(ud->current <= ud->range.stop) return StopIteration();
+    }
+    py_newint(py_retval(), ud->current);
+    ud->current += ud->range.step;
+    return true;
+}
+
+py_Type pk_range_iterator__register() {
+    pk_VM* vm = pk_current_vm;
+    py_Type type = pk_VM__new_type(vm, "range_iterator", tp_object, NULL, false);
+
+    py_bindmagic(type, __new__, _py_range_iterator__new__);
+    py_bindmagic(type, __iter__, _py_range_iterator__iter__);
+    py_bindmagic(type, __next__, _py_range_iterator__next__);
+    return type;
+}

src/public/py_str.c

@@ -521,10 +521,7 @@ static bool _py_str_iterator__next__(int argc, py_Ref argv) {
     int* ud = py_touserdata(&argv[0]);
     int size;
     const char* data = py_tostrn(py_getslot(argv, 0), &size);
-    if(*ud == size) {
-        *py_retval() = pk_current_vm->StopIteration;
-        return true;
-    }
+    if(*ud == size) return StopIteration();
     int start = *ud;
     int len = c11__u8_header(data[*ud], false);
     *ud += len;

src/public/vm.c

@@ -35,6 +35,18 @@ const char* pk_opname(Opcode op) {
     return OP_NAMES[op];
 }
 
+py_TValue* pk_arrayview(py_Ref self, int* length) {
+    if(self->type == tp_list) {
+        *length = py_list__len(self);
+        return py_list__getitem(self, 0);
+    }
+    if(self->type == tp_tuple) {
+        *length = py_tuple__len(self);
+        return py_tuple__getitem(self, 0);
+    }
+    return NULL;
+}
+
 static void disassemble(CodeObject* co) {
     c11_vector /*T=int*/ jumpTargets;
     c11_vector__ctor(&jumpTargets, sizeof(int));
@@ -305,3 +317,10 @@ bool py_callmagic(py_Name name, int argc, py_Ref argv) {
     if(!tmp) return AttributeError(argv, name);
     return py_call(tmp, argc, argv);
 }
+
+bool StopIteration() {
+    pk_VM* vm = pk_current_vm;
+    assert(!vm->is_stopiteration);  // flag is already set
+    vm->is_stopiteration = true;
+    return false;
+}