Fix issue #31; Removed `down_cast`

code/demo.odin

@@ -14,5 +14,9 @@
 #import "utf16.odin";
 
 main :: proc() {
-
+	if x := 0; x < 0 {
+		fmt.println(x);
+	} else {
+		fmt.println(x);
+	}
 }

core/os_windows.odin

@@ -194,9 +194,6 @@ last_write_time_by_name :: proc(name: string) -> File_Time {
 }
 
 
-
-
-
 read_entire_file :: proc(name: string) -> ([]byte, bool) {
 	buf: [300]byte;
 	copy(buf[..], cast([]byte)name);
@@ -208,13 +205,12 @@ read_entire_file :: proc(name: string) -> ([]byte, bool) {
 	defer close(fd);
 
 	length: i64;
-	file_size_ok := win32.GetFileSizeEx(cast(win32.Handle)fd, ^length) != 0;
-	if !file_size_ok {
+	if ok := win32.GetFileSizeEx(cast(win32.Handle)fd, ^length) != 0; !ok {
 		return nil, false;
 	}
 
 	data := make([]byte, length);
-	if ^data[0] == nil {
+	if data == nil {
 		return nil, false;
 	}
 

core/utf16.odin

@@ -0,0 +1,58 @@
+REPLACEMENT_CHAR :: '\uFFFD';
+MAX_RUNE         :: '\U0010FFFF';
+
+_surr1           :: 0xd800;
+_surr2           :: 0xdc00;
+_surr3           :: 0xe000;
+_surr_self       :: 0x10000;
+
+
+is_surrogate :: proc(r: rune) -> bool {
+	return _surr1 <= r && r < _surr3;
+}
+
+decode_surrogate_pair :: proc(r1, r2: rune) -> rune {
+	if _surr1 <= r1 && r1 < _surr2 && _surr2 <= r2 && r2 < _surr3 {
+		return (r1-_surr1)<<10 | (r2 - _surr2) + _surr_self;
+	}
+	return REPLACEMENT_CHAR;
+}
+
+
+encode_surrogate_pair :: proc(r: rune) -> (r1, r2: rune) {
+	if r < _surr_self || r > MAX_RUNE {
+		return REPLACEMENT_CHAR, REPLACEMENT_CHAR;
+	}
+	r -= _surr_self;
+	return _surr1 + (r>>10)&0x3ff, _surr2 + r&0x3ff;
+}
+
+encode :: proc(d: []u16, s: []rune) {
+	n := len(s);
+	for r in s {
+		if r >= _surr_self {
+			n++;
+		}
+	}
+
+	max_n := min(len(d), n);
+	n = 0;
+
+	for r in s {
+		match {
+		case 0 <= r && r < _surr1, _surr3 <= r && r < _surr_self:
+			d[n] = cast(u16)r;
+			n++;
+
+		case _surr_self <= r && r <= MAX_RUNE:
+			r1, r2 := encode_surrogate_pair(r);
+			d[n]    = cast(u16)r1;
+			d[n+1]  = cast(u16)r2;
+			n += 2;
+
+		default:
+			d[n] = cast(u16)REPLACEMENT_CHAR;
+			n++;
+		}
+	}
+}

src/check_expr.c

@@ -3950,7 +3950,7 @@ bool check_builtin_procedure(Checker *c, Operand *operand, AstNode *call, i32 id
 		    id == BuiltinProc_kmag) {
 			if (!is_type_quaternion(x->type)) {
 				gbString s = type_to_string(x->type);
-				error_node(call, "Argument has type `%s`, expected a complex type", s);
+				error_node(call, "Argument has type `%s`, expected a quaternion type", s);
 				gb_string_free(s);
 				return false;
 			}
@@ -5455,71 +5455,6 @@ ExprKind check_expr_base_internal(Checker *c, Operand *o, AstNode *node, Type *t
 			o->type = t;
 			o->mode = Addressing_OptionalOk;
 		} break;
-		case Token_down_cast: {
-			if (o->mode == Addressing_Constant) {
-				gbString expr_str = expr_to_string(o->expr);
-				error_node(o->expr, "Cannot `down_cast` a constant expression: `%s`", expr_str);
-				gb_string_free(expr_str);
-				o->mode = Addressing_Invalid;
-				o->expr = node;
-				return kind;
-			}
-
-			if (is_type_untyped(o->type)) {
-				gbString expr_str = expr_to_string(o->expr);
-				error_node(o->expr, "Cannot `down_cast` an untyped expression: `%s`", expr_str);
-				gb_string_free(expr_str);
-				o->mode = Addressing_Invalid;
-				o->expr = node;
-				return kind;
-			}
-
-			if (!(is_type_pointer(o->type) && is_type_pointer(t))) {
-				gbString expr_str = expr_to_string(o->expr);
-				error_node(o->expr, "Can only `down_cast` pointers: `%s`", expr_str);
-				gb_string_free(expr_str);
-				o->mode = Addressing_Invalid;
-				o->expr = node;
-				return kind;
-			}
-
-			Type *src = type_deref(o->type);
-			Type *dst = type_deref(t);
-			Type *bsrc = base_type(src);
-			Type *bdst = base_type(dst);
-
-			if (!(is_type_struct(bsrc) || is_type_raw_union(bsrc))) {
-				gbString expr_str = expr_to_string(o->expr);
-				error_node(o->expr, "Can only `down_cast` pointer from structs or unions: `%s`", expr_str);
-				gb_string_free(expr_str);
-				o->mode = Addressing_Invalid;
-				o->expr = node;
-				return kind;
-			}
-
-			if (!(is_type_struct(bdst) || is_type_raw_union(bdst))) {
-				gbString expr_str = expr_to_string(o->expr);
-				error_node(o->expr, "Can only `down_cast` pointer to structs or unions: `%s`", expr_str);
-				gb_string_free(expr_str);
-				o->mode = Addressing_Invalid;
-				o->expr = node;
-				return kind;
-			}
-
-			String param_name = check_down_cast_name(dst, src);
-			if (param_name.len == 0) {
-				gbString expr_str = expr_to_string(o->expr);
-				error_node(o->expr, "Illegal `down_cast`: `%s`", expr_str);
-				gb_string_free(expr_str);
-				o->mode = Addressing_Invalid;
-				o->expr = node;
-				return kind;
-			}
-
-			o->mode = Addressing_Value;
-			o->type = t;
-		} break;
-
 
 		default:
 			GB_PANIC("Unknown cast expression");

src/ir.c

@@ -3468,9 +3468,11 @@ irValue *ir_build_expr(irProcedure *proc, AstNode *expr) {
 			ir_emit_comment(proc, str_lit("cast - transmute"));
 			return ir_emit_transmute(proc, e, type);
 
+	#if 0
 		case Token_down_cast:
 			ir_emit_comment(proc, str_lit("cast - down_cast"));
 			return ir_emit_down_cast(proc, e, type);
+	#endif
 
 		case Token_union_cast:
 			ir_emit_comment(proc, str_lit("cast - union_cast"));
@@ -4596,6 +4598,7 @@ irAddr ir_build_addr(irProcedure *proc, AstNode *expr) {
 			ir_emit_store(proc, v, ir_emit_transmute(proc, ir_build_expr(proc, ce->expr), type));
 			return ir_addr(v);
 		}
+	#if 0
 		case Token_down_cast: {
 			ir_emit_comment(proc, str_lit("Cast - down_cast"));
 			// NOTE(bill): Needed for dereference of pointer conversion
@@ -4604,6 +4607,7 @@ irAddr ir_build_addr(irProcedure *proc, AstNode *expr) {
 			ir_emit_store(proc, v, ir_emit_down_cast(proc, ir_build_expr(proc, ce->expr), type));
 			return ir_addr(v);
 		}
+	#endif
 		case Token_union_cast: {
 			ir_emit_comment(proc, str_lit("Cast - union_cast"));
 			// NOTE(bill): Needed for dereference of pointer conversion

src/parser.c

@@ -2056,7 +2056,6 @@ AstNode *parse_unary_expr(AstFile *f, bool lhs) {
 
 	case Token_cast:
 	case Token_transmute:
-	case Token_down_cast:
 	case Token_union_cast:
 	{
 		Token token = f->curr_token; next_token(f);

src/tokenizer.c

@@ -108,7 +108,6 @@ TOKEN_KIND(Token__KeywordBegin, "_KeywordBegin"), \
 	TOKEN_KIND(Token_immutable,      "immutable"),           \
 	TOKEN_KIND(Token_cast,           "cast"),                \
 	TOKEN_KIND(Token_transmute,      "transmute"),           \
-	TOKEN_KIND(Token_down_cast,      "down_cast"),           \
 	TOKEN_KIND(Token_union_cast,     "union_cast"),          \
 	TOKEN_KIND(Token_context,        "context"),             \
 	TOKEN_KIND(Token_push_context,   "push_context"),        \