Revert demo

examples/demo.odin

@@ -20,10 +20,759 @@ when ODIN_OS == "windows" {
 	import win32 "core:sys/windows.odin"
 }
 
-main :: proc() {
-	fmt.println("Hellope");
+@(link_name="general_stuff")
+general_stuff :: proc() {
+	fmt.println("# general_stuff");
+	{ // `do` for inline statements rather than block
+		foo :: proc() do fmt.println("Foo!");
+		if   false do foo();
+		for  false do foo();
+		when false do foo();
 
-	i := -10;
-	x := make([dynamic]int, 0, i);
-	fmt.println(x);
+		if false do foo();
+		else     do foo();
+	}
+
+	{ // Removal of `++` and `--` (again)
+		x: int;
+		x += 1;
+		x -= 1;
+	}
+	{ // Casting syntaxes
+		i := i32(137);
+		ptr := &i;
+
+		_ = (^f32)(ptr);
+		// ^f32(ptr) == ^(f32(ptr))
+		_ = cast(^f32)ptr;
+
+		_ = (^f32)(ptr)^;
+		_ = (cast(^f32)ptr)^;
+
+		// Questions: Should there be two ways to do it?
+	}
+
+	/*
+	 * Remove *_val_of built-in procedures
+	 * size_of, align_of, offset_of
+	 * type_of, type_info_of
+	 */
+
+	{ // `expand_to_tuple` built-in procedure
+		Foo :: struct {
+			x: int,
+			b: bool,
+		}
+		f := Foo{137, true};
+		x, b := expand_to_tuple(f);
+		fmt.println(f);
+		fmt.println(x, b);
+		fmt.println(expand_to_tuple(f));
+	}
+
+	{
+		// ..  half-closed range
+		// ... open range
+
+		for in 0..2  {} // 0, 1
+		for in 0...2 {} // 0, 1, 2
+	}
+
+	{ // Multiple sized booleans
+
+		x0: bool; // default
+		x1: b8  = true;
+		x2: b16 = false;
+		x3: b32 = true;
+		x4: b64 = false;
+
+		fmt.printf("x1: %T = %v;\n", x1, x1);
+		fmt.printf("x2: %T = %v;\n", x2, x2);
+		fmt.printf("x3: %T = %v;\n", x3, x3);
+		fmt.printf("x4: %T = %v;\n", x4, x4);
+
+		// Having specific sized booleans is very useful when dealing with foreign code
+		// and to enforce specific alignment for a boolean, especially within a struct
+	}
+
+	{ // `distinct` types
+		// Originally, all type declarations would create a distinct type unless #type_alias was present.
+		// Now the behaviour has been reversed. All type declarations create a type alias unless `distinct` is present.
+		// If the type expression is `struct`, `union`, `enum`, `proc`, or `bit_field`, the types will always been distinct.
+
+		Int32 :: i32;
+		#assert(Int32 == i32);
+
+		My_Int32 :: distinct i32;
+		#assert(My_Int32 != i32);
+
+		My_Struct :: struct{x: int};
+		#assert(My_Struct != struct{x: int});
+	}
+}
+
+default_struct_values :: proc() {
+	fmt.println("# default_struct_values");
+	{
+		Vector3 :: struct {
+			x: f32,
+			y: f32,
+			z: f32,
+		}
+		v: Vector3;
+		fmt.println(v);
+	}
+	{
+		// Default values must be constants
+		Vector3 :: struct {
+			x: f32 = 1,
+			y: f32 = 4,
+			z: f32 = 9,
+		}
+		v: Vector3;
+		fmt.println(v);
+
+		v = Vector3{};
+		fmt.println(v);
+
+		// Uses the same semantics as a default values in a procedure
+		v = Vector3{137};
+		fmt.println(v);
+
+		v = Vector3{z = 137};
+		fmt.println(v);
+	}
+
+	{
+		Vector3 :: struct {
+			x := 1.0,
+			y := 4.0,
+			z := 9.0,
+		}
+		stack_default: Vector3;
+		stack_literal := Vector3{};
+		heap_one      := new(Vector3);         defer free(heap_one);
+		heap_two      := new_clone(Vector3{}); defer free(heap_two);
+
+		fmt.println("stack_default  - ", stack_default);
+		fmt.println("stack_literal  - ", stack_literal);
+		fmt.println("heap_one       - ", heap_one^);
+		fmt.println("heap_two       - ", heap_two^);
+
+
+		N :: 4;
+		stack_array: [N]Vector3;
+		heap_array := new([N]Vector3);    defer free(heap_array);
+		heap_slice := make([]Vector3, N); defer free(heap_slice);
+		fmt.println("stack_array[1] - ", stack_array[1]);
+		fmt.println("heap_array[1]  - ", heap_array[1]);
+		fmt.println("heap_slice[1]  - ", heap_slice[1]);
+	}
+}
+
+
+
+
+union_type :: proc() {
+	fmt.println("\n# union_type");
+	{
+		val: union{int, bool};
+		val = 137;
+		if i, ok := val.(int); ok {
+			fmt.println(i);
+		}
+		val = true;
+		fmt.println(val);
+
+		val = nil;
+
+		switch v in val {
+		case int:  fmt.println("int",  v);
+		case bool: fmt.println("bool", v);
+		case:      fmt.println("nil");
+		}
+	}
+	{
+		// There is a duality between `any` and `union`
+		// An `any` has a pointer to the data and allows for any type (open)
+		// A `union` has as binary blob to store the data and allows only certain types (closed)
+		// The following code is with `any` but has the same syntax
+		val: any;
+		val = 137;
+		if i, ok := val.(int); ok {
+			fmt.println(i);
+		}
+		val = true;
+		fmt.println(val);
+
+		val = nil;
+
+		switch v in val {
+		case int:  fmt.println("int",  v);
+		case bool: fmt.println("bool", v);
+		case:      fmt.println("nil");
+		}
+	}
+
+	Vector3 :: struct {x, y, z: f32};
+	Quaternion :: struct {x, y, z: f32, w: f32 = 1};
+
+	// More realistic examples
+	{
+		// NOTE(bill): For the above basic examples, you may not have any
+		// particular use for it. However, my main use for them is not for these
+		// simple cases. My main use is for hierarchical types. Many prefer
+		// subtyping, embedding the base data into the derived types. Below is
+		// an example of this for a basic game Entity.
+
+		Entity :: struct {
+			id:          u64,
+			name:        string,
+			position:    Vector3,
+			orientation: Quaternion,
+
+			derived: any,
+		}
+
+		Frog :: struct {
+			using entity: Entity,
+			jump_height:  f32,
+		}
+
+		Monster :: struct {
+			using entity: Entity,
+			is_robot:     bool,
+			is_zombie:    bool,
+		}
+
+		// See `parametric_polymorphism` procedure for details
+		new_entity :: proc(T: type) -> ^Entity {
+			t := new(T);
+			t.derived = t^;
+			return t;
+		}
+
+		entity := new_entity(Monster);
+
+		switch e in entity.derived {
+		case Frog:
+			fmt.println("Ribbit");
+		case Monster:
+			if e.is_robot  do fmt.println("Robotic");
+			if e.is_zombie do fmt.println("Grrrr!");
+		}
+	}
+
+	{
+		// NOTE(bill): A union can be used to achieve something similar. Instead
+		// of embedding the base data into the derived types, the derived data
+		// in embedded into the base type. Below is the same example of the
+		// basic game Entity but using an union.
+
+		Entity :: struct {
+			id:          u64,
+			name:        string,
+			position:    Vector3,
+			orientation: Quaternion,
+
+			derived: union {Frog, Monster},
+		}
+
+		Frog :: struct {
+			using entity: ^Entity,
+			jump_height:  f32,
+		}
+
+		Monster :: struct {
+			using entity: ^Entity,
+			is_robot:     bool,
+			is_zombie:    bool,
+		}
+
+		// See `parametric_polymorphism` procedure for details
+		new_entity :: proc(T: type) -> ^Entity {
+			t := new(Entity);
+			t.derived = T{entity = t};
+			return t;
+		}
+
+		entity := new_entity(Monster);
+
+		switch e in entity.derived {
+		case Frog:
+			fmt.println("Ribbit");
+		case Monster:
+			if e.is_robot  do fmt.println("Robotic");
+			if e.is_zombie do fmt.println("Grrrr!");
+		}
+
+		// NOTE(bill): As you can see, the usage code has not changed, only its
+		// memory layout. Both approaches have their own advantages but they can
+		// be used together to achieve different results. The subtyping approach
+		// can allow for a greater control of the memory layout and memory
+		// allocation, e.g. storing the derivatives together. However, this is
+		// also its disadvantage. You must either preallocate arrays for each
+		// derivative separation (which can be easily missed) or preallocate a
+		// bunch of "raw" memory; determining the maximum size of the derived
+		// types would require the aid of metaprogramming. Unions solve this
+		// particular problem as the data is stored with the base data.
+		// Therefore, it is possible to preallocate, e.g. [100]Entity.
+
+		// It should be noted that the union approach can have the same memory
+		// layout as the any and with the same type restrictions by using a
+		// pointer type for the derivatives.
+
+		/*
+			Entity :: struct {
+				...
+				derived: union{^Frog, ^Monster},
+			}
+
+			Frog :: struct {
+				using entity: Entity,
+				...
+			}
+			Monster :: struct {
+				using entity: Entity,
+				...
+
+			}
+			new_entity :: proc(T: type) -> ^Entity {
+				t := new(T);
+				t.derived = t;
+				return t;
+			}
+		*/
+	}
+}
+
+parametric_polymorphism :: proc() {
+	fmt.println("# parametric_polymorphism");
+
+	print_value :: proc(value: $T) {
+		fmt.printf("print_value: %T %v\n", value, value);
+	}
+
+	v1: int    = 1;
+	v2: f32    = 2.1;
+	v3: f64    = 3.14;
+	v4: string = "message";
+
+	print_value(v1);
+	print_value(v2);
+	print_value(v3);
+	print_value(v4);
+
+	fmt.println();
+
+	add :: proc(p, q: $T) -> T {
+		x: T = p + q;
+		return x;
+	}
+
+	a := add(3, 4);
+	fmt.printf("a: %T = %v\n", a, a);
+
+	b := add(3.2, 4.3);
+	fmt.printf("b: %T = %v\n", b, b);
+
+	// This is how `new` is implemented
+	alloc_type :: proc(T: type) -> ^T {
+		t := cast(^T)alloc(size_of(T), align_of(T));
+		t^ = T{}; // Use default initialization value
+		return t;
+	}
+
+	copy_slice :: proc(dst, src: []$T) -> int {
+		return mem.copy(&dst[0], &src[0], n*size_of(T));
+	}
+
+	double_params :: proc(a: $A, b: $B) -> A {
+		return a + A(b);
+	}
+
+	fmt.println(double_params(12, 1.345));
+
+
+
+	{ // Polymorphic Types and Type Specialization
+		Table_Slot :: struct(Key, Value: type) {
+			occupied: bool,
+			hash:     u32,
+			key:      Key,
+			value:    Value,
+		}
+		TABLE_SIZE_MIN :: 32;
+		Table :: struct(Key, Value: type) {
+			count:     int,
+			allocator: Allocator,
+			slots:     []Table_Slot(Key, Value),
+		}
+
+		// Only allow types that are specializations of a (polymorphic) slice
+		make_slice :: proc(T: type/[]$E, len: int) -> T {
+			return make(T, len);
+		}
+
+
+		// Only allow types that are specializations of `Table`
+		allocate :: proc(table: ^$T/Table, capacity: int) {
+			c := context;
+			if table.allocator.procedure != nil do c.allocator = table.allocator;
+
+			context <- c {
+				table.slots = make_slice(type_of(table.slots), max(capacity, TABLE_SIZE_MIN));
+			}
+		}
+
+		expand :: proc(table: ^$T/Table) {
+			c := context;
+			if table.allocator.procedure != nil do c.allocator = table.allocator;
+
+			context <- c {
+				old_slots := table.slots;
+
+				cap := max(2*len(table.slots), TABLE_SIZE_MIN);
+				allocate(table, cap);
+
+				for s in old_slots do if s.occupied {
+					put(table, s.key, s.value);
+				}
+
+				free(old_slots);
+			}
+		}
+
+		// Polymorphic determination of a polymorphic struct
+		// put :: proc(table: ^$T/Table, key: T.Key, value: T.Value) {
+		put :: proc(table: ^Table($Key, $Value), key: Key, value: Value) {
+			hash := get_hash(key); // Ad-hoc method which would fail in a different scope
+			index := find_index(table, key, hash);
+			if index < 0 {
+				if f64(table.count) >= 0.75*f64(len(table.slots)) {
+					expand(table);
+				}
+				assert(table.count <= len(table.slots));
+
+				hash := get_hash(key);
+				index = int(hash % u32(len(table.slots)));
+
+				for table.slots[index].occupied {
+					if index += 1; index >= len(table.slots) {
+						index = 0;
+					}
+				}
+
+				table.count += 1;
+			}
+
+			slot := &table.slots[index];
+			slot.occupied = true;
+			slot.hash     = hash;
+			slot.key      = key;
+			slot.value    = value;
+		}
+
+
+		// find :: proc(table: ^$T/Table, key: T.Key) -> (T.Value, bool) {
+		find :: proc(table: ^Table($Key, $Value), key: Key) -> (Value, bool) {
+			hash := get_hash(key);
+			index := find_index(table, key, hash);
+			if index < 0 {
+				return Value{}, false;
+			}
+			return table.slots[index].value, true;
+		}
+
+		find_index :: proc(table: ^Table($Key, $Value), key: Key, hash: u32) -> int {
+			if len(table.slots) <= 0 do return -1;
+
+			index := int(hash % u32(len(table.slots)));
+			for table.slots[index].occupied {
+				if table.slots[index].hash == hash {
+					if table.slots[index].key == key {
+						return index;
+					}
+				}
+
+				if index += 1; index >= len(table.slots) {
+					index = 0;
+				}
+			}
+
+			return -1;
+		}
+
+		get_hash :: proc(s: string) -> u32 { // fnv32a
+			h: u32 = 0x811c9dc5;
+			for i in 0..len(s) {
+				h = (h ~ u32(s[i])) * 0x01000193;
+			}
+			return h;
+		}
+
+
+		table: Table(string, int);
+
+		for i in 0..36 do put(&table, "Hellope", i);
+		for i in 0..42 do put(&table, "World!",  i);
+
+		found, _ := find(&table, "Hellope");
+		fmt.printf("`found` is %v\n", found);
+
+		found, _ = find(&table, "World!");
+		fmt.printf("`found` is %v\n", found);
+
+		// I would not personally design a hash table like this in production
+		// but this is a nice basic example
+		// A better approach would either use a `u64` or equivalent for the key
+		// and let the user specify the hashing function or make the user store
+		// the hashing procedure with the table
+	}
+}
+
+
+
+
+prefix_table := [?]string{
+	"White",
+	"Red",
+	"Green",
+	"Blue",
+	"Octarine",
+	"Black",
+};
+
+threading_example :: proc() {
+	when ODIN_OS == "windows" {
+		fmt.println("# threading_example");
+
+		unordered_remove :: proc(array: ^[dynamic]$T, index: int, loc := #caller_location) {
+			__bounds_check_error_loc(loc, index, len(array));
+			array[index] = array[len(array)-1];
+			pop(array);
+		}
+		ordered_remove :: proc(array: ^[dynamic]$T, index: int, loc := #caller_location) {
+			__bounds_check_error_loc(loc, index, len(array));
+			copy(array[index..], array[index+1..]);
+			pop(array);
+		}
+
+		worker_proc :: proc(t: ^thread.Thread) -> int {
+			for iteration in 1...5 {
+				fmt.printf("Thread %d is on iteration %d\n", t.user_index, iteration);
+				fmt.printf("`%s`: iteration %d\n", prefix_table[t.user_index], iteration);
+				// win32.sleep(1);
+			}
+			return 0;
+		}
+
+		threads := make([dynamic]^thread.Thread, 0, len(prefix_table));
+		defer free(threads);
+
+		for in prefix_table {
+			if t := thread.create(worker_proc); t != nil {
+				t.init_context = context;
+				t.use_init_context = true;
+				t.user_index = len(threads);
+				append(&threads, t);
+				thread.start(t);
+			}
+		}
+
+		for len(threads) > 0 {
+			for i := 0; i < len(threads); /**/ {
+				if t := threads[i]; thread.is_done(t) {
+					fmt.printf("Thread %d is done\n", t.user_index);
+					thread.destroy(t);
+
+					ordered_remove(&threads, i);
+				} else {
+					i += 1;
+				}
+			}
+		}
+	}
+}
+
+array_programming :: proc() {
+	fmt.println("# array_programming");
+	{
+		a := [3]f32{1, 2, 3};
+		b := [3]f32{5, 6, 7};
+		c := a * b;
+		d := a + b;
+		e := 1 +  (c - d) / 2;
+		fmt.printf("%.1f\n", e); // [0.5, 3.0, 6.5]
+	}
+
+	{
+		a := [3]f32{1, 2, 3};
+		b := swizzle(a, 2, 1, 0);
+		assert(b == [3]f32{3, 2, 1});
+
+		c := swizzle(a, 0, 0);
+		assert(c == [2]f32{1, 1});
+		assert(c == 1);
+	}
+
+	{
+		Vector3 :: distinct [3]f32;
+		a := Vector3{1, 2, 3};
+		b := Vector3{5, 6, 7};
+		c := (a * b)/2 + 1;
+		d := c.x + c.y + c.z;
+		fmt.printf("%.1f\n", d); // 22.0
+
+		cross :: proc(a, b: Vector3) -> Vector3 {
+			i := swizzle(a, 1, 2, 0) * swizzle(b, 2, 0, 1);
+			j := swizzle(a, 2, 0, 1) * swizzle(b, 1, 2, 0);
+			return i - j;
+		}
+
+		blah :: proc(a: Vector3) -> f32 {
+			return a.x + a.y + a.z;
+		}
+
+		x := cross(a, b);
+		fmt.println(x);
+		fmt.println(blah(x));
+	}
+}
+
+
+using println in import "core:fmt.odin"
+
+using_in :: proc() {
+	fmt.println("# using in");
+	using print in fmt;
+
+	println("Hellope1");
+	print("Hellope2\n");
+
+	Foo :: struct {
+		x, y: int,
+		b: bool,
+	}
+	f: Foo;
+	f.x, f.y = 123, 321;
+	println(f);
+	using x, y in f;
+	x, y = 456, 654;
+	println(f);
+}
+
+named_proc_return_parameters :: proc() {
+	fmt.println("# named proc return parameters");
+
+	foo0 :: proc() -> int {
+		return 123;
+	}
+	foo1 :: proc() -> (a: int) {
+		a = 123;
+		return;
+	}
+	foo2 :: proc() -> (a, b: int) {
+		// Named return values act like variables within the scope
+		a = 321;
+		b = 567;
+		return b, a;
+	}
+	fmt.println("foo0 =", foo0()); // 123
+	fmt.println("foo1 =", foo1()); // 123
+	fmt.println("foo2 =", foo2()); // 567 321
+}
+
+
+enum_export :: proc() {
+	fmt.println("# enum #export");
+
+	Foo :: enum #export {A, B, C};
+
+	f0 := A;
+	f1 := B;
+	f2 := C;
+	fmt.println(f0, f1, f2);
+}
+
+explicit_procedure_overloading :: proc() {
+	fmt.println("# explicit procedure overloading");
+
+	add_ints :: proc(a, b: int) -> int {
+		x := a + b;
+		fmt.println("add_ints", x);
+		return x;
+	}
+	add_floats :: proc(a, b: f32) -> f32 {
+		x := a + b;
+		fmt.println("add_floats", x);
+		return x;
+	}
+	add_numbers :: proc(a: int, b: f32, c: u8) -> int {
+		x := int(a) + int(b) + int(c);
+		fmt.println("add_numbers", x);
+		return x;
+	}
+
+	add :: proc[add_ints, add_floats, add_numbers];
+
+	add(int(1), int(2));
+	add(f32(1), f32(2));
+	add(int(1), f32(2), u8(3));
+
+	add(1, 2);     // untyped ints coerce to int tighter than f32
+	add(1.0, 2.0); // untyped floats coerce to f32 tighter than int
+	add(1, 2, 3);  // three parameters
+
+	// Ambiguous answers
+	// add(1.0, 2);
+	// add(1, 2.0);
+}
+
+complete_switch :: proc() {
+	fmt.println("# complete_switch");
+	{ // enum
+		Foo :: enum #export {
+			A,
+			B,
+			C,
+			D,
+		}
+
+		b := Foo.B;
+		f := Foo.A;
+		#complete switch f {
+		case A: fmt.println("A");
+		case B: fmt.println("B");
+		case C: fmt.println("C");
+		case D: fmt.println("D");
+		case:   fmt.println("?");
+		}
+	}
+	{ // union
+		Foo :: union {int, bool};
+		f: Foo = 123;
+		#complete switch in f {
+		case int:  fmt.println("int");
+		case bool: fmt.println("bool");
+		case:
+		}
+	}
+}
+
+
+main :: proc() {
+	when false {
+		general_stuff();
+		default_struct_values();
+		union_type();
+		parametric_polymorphism();
+		threading_example();
+		array_programming();
+		using_in();
+		named_proc_return_parameters();
+		enum_export();
+		explicit_procedure_overloading();
+		complete_switch();
+	}
 }

src/build_settings.cpp

@@ -345,7 +345,7 @@ void init_build_context(void) {
 
 	{
 		u16 x = 1;
-		bool big = !bit_cast<u8>(x);
+		bool big = !*cast(u8 *)&x;
 		bc->ODIN_ENDIAN = big ? str_lit("big") : str_lit("little");
 	}