New faults and syntax (#2034)

- Remove `[?]` syntax.
- Change `int!` to `int?` syntax.
- New `fault` declarations.
- Enum associated values can reference the calling enum.

resources/examples/base64.c3

@@ -1,11 +1,10 @@
 module base64;
+
+fault INVALID_CHARACTER;
+
 // Based on the C2 version.
 
 
-fault DecodingError
-{
-	INVALID_CHARACTER
-}
 const char[64] LUT_ENC = {
 	'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H',
 	'I', 'J', 'K', 'L', 'M', 'N', 'O', 'P',
@@ -76,7 +75,7 @@ fn void encode(char[] in, char *out)
 }
 
 
-fn int! decode(String in, char* out, int* invalid_char_index = null)
+fn int? decode(String in, char* out, int* invalid_char_index = null)
 {
 	int j = 0;
 
@@ -89,7 +88,7 @@ fn int! decode(String in, char* out, int* invalid_char_index = null)
 		if (c == ERR)
 		{
 			if (invalid_char_index) *invalid_char_index = i;
-			return DecodingError.INVALID_CHARACTER?;
+			return INVALID_CHARACTER?;
 		}
 
 
@@ -127,7 +126,7 @@ fn void main()
 	encode(helloworld[0..12], &buffer);
 	printf("Result: %s\n", &buffer);
 	char *to_decode = "aGVsbG8gd29ybGRcMA==";
-	char[?] result = b64"aGVsbG8gd29ybGRcMA==";
+	char[*] result = b64"aGVsbG8gd29ybGRcMA==";
 	decode((String)to_decode[0..19], &buffer)!!;
 	printf("Result: %s\n", &buffer);
 	printf("Result direct: %.*s\n", 13, &result);

resources/examples/brainfk.c3

@@ -4,18 +4,15 @@ import std::io;
 const BF_MEM = 30000;
 char[BF_MEM] memory;
 
-fault InterpretError
-{
-	INTEPRET_FAILED
-}
+fault INTEPRET_FAILED;
 
-fn void! print_error_type_at(usz pos, String err)
+fn void? print_error_type_at(usz pos, String err)
 {
 	io::printfn("Error at %s: %s", pos, err);
-	return InterpretError.INTEPRET_FAILED?;
+	return INTEPRET_FAILED?;
 }
 
-fn void! brainf(String program)
+fn void? brainf(String program)
 {
 	usz sp = 0;
 	usz mem = 0;

resources/examples/contextfree/boolerr.c3

@@ -4,15 +4,8 @@ import libc;
 import std::io;
 import std::collections::maybe;
 
-fault TitleResult
-{
-	TITLE_MISSING
-}
-
-fault ReadError
-{
-	BAD_READ,
-}
+fault TITLE_MISSING;
+fault BAD_READ;
 
 struct Doc
 {
@@ -30,14 +23,14 @@ struct Summary
 	bool ok;
 }
 
-fn void! Summary.print(Summary* s, OutStream out)
+fn void? Summary.print(Summary* s, OutStream out)
 {
 	io::fprintf(out, "Summary({ .title = %s, .ok = %s})", s.title.get() ?? "missing", s.ok)!;
 }
 
-fn Doc! read_doc(String url)
+fn Doc? read_doc(String url)
 {
-	if (url.contains("fail")) return ReadError.BAD_READ?;
+	if (url.contains("fail")) return BAD_READ?;
 	if (url.contains("head-missing")) return { };
 	if (url.contains("title-missing")) return { .head = maybe::value{Head}({}) };
 	if (url.contains("title-empty")) return { .head = maybe::value{Head}({ .title = maybe::value{String}("")}) };
@@ -57,14 +50,14 @@ fn Summary read_and_build_summary(String url)
 	return build_summary(read_doc(url)) ?? {};
 }
 
-fn bool! is_title_non_empty(Doc doc)
+fn bool? is_title_non_empty(Doc doc)
 {
-	String! title = doc.head.get().title.get();
-	if (catch title) return TitleResult.TITLE_MISSING?;
+	String? title = doc.head.get().title.get();
+	if (catch title) return TITLE_MISSING?;
 	return title.len > 0;
 }
 
-fn bool! read_whether_title_non_empty(String url)
+fn bool? read_whether_title_non_empty(String url)
 {
     return is_title_non_empty(read_doc(url));
 }
@@ -90,7 +83,7 @@ fn void main()
             summary.print(out)!!;
             io::fprintn(out, "")!!;
             io::fprintf(out, "  Title: %s\n", summary.title.get() ?? "")!!;
-            bool! has_title = read_whether_title_non_empty(url);
+            bool? has_title = read_whether_title_non_empty(url);
             // This looks a bit less than elegant, but as you see it's mostly due to having to
             // use printf here.
             io::fprintf(out, "  Has title: %s vs %s\n", bool_to_string(has_title) ?? (@catch(has_title)).nameof, has_title ?? false)!!;

resources/examples/contextfree/cleanup.c3

@@ -6,12 +6,9 @@ struct Resource
 	String name;
 }
 
-fault Error
-{
-	WELCOME_TO_YOUR_DOOM
-}
+fault WELCOME_TO_YOUR_DOOM;
 
-fn Resource! resource_init(String name)
+fn Resource? resource_init(String name)
 {
 	io::printfn("open %s", name);
 	return { name };
@@ -19,7 +16,7 @@ fn Resource! resource_init(String name)
 
 fn void Resource.deinit(Resource this) => io::printfn("close %s", this.name);
 
-macro void! @open_with(String name; @body(Resource resource))
+macro void? @open_with(String name; @body(Resource resource))
 {
 	Resource resource = resource_init(name)!;
 	defer
@@ -30,7 +27,7 @@ macro void! @open_with(String name; @body(Resource resource))
 	@body(resource);
 }
 
-fn Resource! prep_out(String out_name, String[] prep_names)
+fn Resource? prep_out(String out_name, String[] prep_names)
 {
 	Resource writer = resource_init(out_name)!; // Rethrow the optional result
 	defer catch writer.deinit();
@@ -39,7 +36,7 @@ fn Resource! prep_out(String out_name, String[] prep_names)
 		@open_with(name; Resource reader)
 		{
 	        io::printfn("use %s", reader.name);
-	        // if (true) return Error.WELCOME_TO_YOUR_DOOM?;
+	        // if (true) return WELCOME_TO_YOUR_DOOM?;
 		}!;
 	}
 	return writer;

resources/examples/contextfree/guess_number.c3

@@ -11,27 +11,23 @@ struct Game
 	int high;
 }
 
-fault InputResult
-{
-	NOT_AN_INT,
-	FAILED_TO_READ,
-}
+fault NOT_AN_INT, FAILED_TO_READ;
 
 int err_count = 0;
 
-fn int! ask_guess(int high)
+fn int? ask_guess(int high)
 {
 	io::printf("Guess a number between 1 and %d: ", high);
-	String text = io::treadline() ?? InputResult.FAILED_TO_READ?!;
-	return text.to_int() ?? InputResult.NOT_AN_INT?;
+	String text = io::treadline() ?? FAILED_TO_READ?!;
+	return text.to_int() ?? NOT_AN_INT?;
 }
 
-fn int! ask_guess_multi(int high)
+fn int? ask_guess_multi(int high)
  {
 	while (true)
 	{
-		int! result = ask_guess(high);
-		if (@catch(result) == InputResult.NOT_AN_INT)
+		int? result = ask_guess(high);
+		if (@catch(result) == NOT_AN_INT)
 		{
 		  io::printn("I didn't understand that.");
 		  err_count++;
@@ -41,7 +37,7 @@ fn int! ask_guess_multi(int high)
 	}
 }
 
-fn void! Game.play(Game *game)
+fn void? Game.play(Game *game)
 {
 	while (!game.done)
 	{

resources/examples/dynlib-test/add.c3

@@ -4,7 +4,7 @@ struct Foo(Printable)
 	int a;
 }
 
-fn usz! Foo.to_format(&self, Formatter* f) @dynamic
+fn usz? Foo.to_format(&self, Formatter* f) @dynamic
 {
 	return f.printf("Foo[%d]", self.a);
 }

resources/examples/map.c3

@@ -1,10 +1,8 @@
 module std::container::map{Key, Type};
 import std::core::builtin;
 import std::io;
-fault MapResult
-{
-	KEY_NOT_FOUND
-}
+
+fault KEY_NOT_FOUND;
 
 struct Entry
 {
@@ -33,22 +31,22 @@ fn void Map.init(Map *map, uint capacity = 128)
     map.mod = capacity - 1;
 }
 
-fn Type! Map.valueForKey(Map *map, Key key)
+fn Type? Map.valueForKey(Map *map, Key key)
 {
-    if (!map.map) return MapResult.KEY_NOT_FOUND?;
+    if (!map.map) return KEY_NOT_FOUND?;
     uint hash = key.hash();
     usz pos = hash & map.mod;
     Entry* entry = &map.map[pos];
-    if (!entry) return MapResult.KEY_NOT_FOUND?;
+    if (!entry) return KEY_NOT_FOUND?;
     while (entry)
     {
         if (entry.hash == hash && entry.key == key) return entry.value;
         entry = entry.next;
     }
-    return MapResult.KEY_NOT_FOUND?;
+    return KEY_NOT_FOUND?;
 }
 
-fn Type! Map.set(Map *map, Key key, Type value) @maydiscard
+fn Type? Map.set(Map *map, Key key, Type value) @maydiscard
 {
 	if (!map.map)
     {
@@ -67,7 +65,7 @@ fn Type! Map.set(Map *map, Key key, Type value) @maydiscard
             entry.value = value;
             entry.hash = hash;
             entry.key = key;
-            return MapResult.KEY_NOT_FOUND?;
+            return KEY_NOT_FOUND?;
         }
         if (entry.hash == hash && entry.key == key)
         {
@@ -87,7 +85,7 @@ fn Type! Map.set(Map *map, Key key, Type value) @maydiscard
         new.next = null;
         new.used = true;
         entry.next = new;
-        return MapResult.KEY_NOT_FOUND?;
+        return KEY_NOT_FOUND?;
     }
 }
 

resources/examples/nbodies.c3

@@ -81,7 +81,7 @@ fn void offset_momentum(Planet[] bodies)
 	bodies[0].vz = - pz / SOLAR_MASS;
 }
 
-Planet[?] planet_bodies = {
+Planet[*] planet_bodies = {
 	{							   /* sun */
 		0, 0, 0, 0, 0, 0, SOLAR_MASS
     },

resources/examples/plus_minus.c3

@@ -2,10 +2,7 @@ module test;
 import std::io;
 import libc;
 
-fault TokenResult
-{
-	NO_MORE_TOKENS
-}
+fault NO_MORE_TOKENS;
 
 
 // While we could have written this with libc
@@ -36,7 +33,7 @@ fn void main(String[] args)
 		val = add ? val + i : val - i;
 
 		// Read an optional token.
-		String! op = read_next(&numbers);
+		String? op = read_next(&numbers);
 
 		// If it's an error, then we're done.
 		if (catch op) break;
@@ -56,7 +53,7 @@ fn void main(String[] args)
 	io::printfn("%d", val);
 }
 
-fn String! read_next(String* remaining)
+fn String? read_next(String* remaining)
 {
 	while (remaining.len > 0 && (*remaining)[0] == ' ')
 	{
@@ -77,7 +74,7 @@ fn String! read_next(String* remaining)
 	}
 
 	// If it's a zero length token, return an optional result.
-	if (!len) return TokenResult.NO_MORE_TOKENS?;
+	if (!len) return NO_MORE_TOKENS?;
 
 	// Otherwise create a slice from the pointer start and length.
 	return (String)ptr_start[:len];

resources/examples/raylib/raylib_snake.c3

@@ -76,7 +76,7 @@ fn void init_game()
 
     counter_tail = 1;
     allow_move = false;
-	snake_direction = SnakeDirection.RIGHT;
+	snake_direction = RIGHT;
     offset.x = SCREEN_WIDTH % SQUARE_SIZE;
     offset.y = SCREEN_HEIGHT % SQUARE_SIZE;
 

resources/examples/raylib/raylib_tetris.c3

@@ -257,7 +257,7 @@ fn void update_game()
     {
         for (int i = 1; i < GRID_HORIZONTAL_SIZE - 1; i++)
         {
-            if (grid[i][j] == GridSquare.FULL)
+            if (grid[i][j] == FULL)
             {
                 game_over = true;
             }
@@ -404,7 +404,7 @@ fn bool create_piece()
     {
         for (int j = 0; j < 4; j++)
         {
-            if (piece[i - (int)piece_position_x][j] == GridSquare.MOVING) grid[i][j] = MOVING;
+            if (piece[i - (int)piece_position_x][j] == MOVING) grid[i][j] = MOVING;
         }
     }
 
@@ -474,7 +474,7 @@ fn void resolve_falling_movement(bool* detection_ref, bool* piece_active_ref)
         {
             for (int i = 1; i < GRID_HORIZONTAL_SIZE - 1; i++)
             {
-                if (grid[i][j] == GridSquare.MOVING)
+                if (grid[i][j] == MOVING)
                 {
                     grid[i][j] = FULL;
                     *detection_ref = false;
@@ -489,7 +489,7 @@ fn void resolve_falling_movement(bool* detection_ref, bool* piece_active_ref)
         {
             for (int i = 1; i < GRID_HORIZONTAL_SIZE - 1; i++)
             {
-                if (grid[i][j] == GridSquare.MOVING)
+                if (grid[i][j] == MOVING)
                 {
                     grid[i][j+1] = MOVING;
                     grid[i][j] = EMPTY;
@@ -513,10 +513,10 @@ fn bool resolve_lateral_movement()
         {
             for (int i = 1; i < GRID_HORIZONTAL_SIZE - 1; i++)
             {
-                if (grid[i][j] == GridSquare.MOVING)
+                if (grid[i][j] == MOVING)
                 {
                     // Check if we are touching the left wall or we have a full square at the left
-                    if ((i-1 == 0) || (grid[i-1][j] == GridSquare.FULL)) collision = true;
+                    if ((i-1 == 0) || (grid[i-1][j] == FULL)) collision = true;
                 }
             }
         }

resources/examples/retry.c3

@@ -1,15 +1,12 @@
 module test;
 import libc;
 
-fault TestErr
-{
-	NOPE
-}
+fault NOPE;
 
-fn int! eventually_succeed()
+fn int? eventually_succeed()
 {
 	static int i = 0;
-	if (i++ < 3) return TestErr.NOPE?;
+	if (i++ < 3) return NOPE?;
 	return i * 3;
 }
 
@@ -19,7 +16,7 @@ macro @retry(#function, int retries = 3)
     anyfault e;
     do
     {
-        $Type! result = #function;
+        $Type? result = #function;
         if (catch err = result)
         {
             e = err;
@@ -32,7 +29,7 @@ macro @retry(#function, int retries = 3)
 
 fn void main()
 {
-    int! result = @retry(eventually_succeed());
+    int? result = @retry(eventually_succeed());
     if (try result)
     {
 	    libc::printf("Got result: %d\n", result);

resources/examples/staticlib-test/add.c3

@@ -5,7 +5,7 @@ struct Foo(Printable)
 	int a;
 }
 
-fn usz! Foo.to_format(&self, Formatter* f) @dynamic
+fn usz? Foo.to_format(&self, Formatter* f) @dynamic
 {
 	return f.printf("Foo[%d]", self.a);
 }

resources/grammar/grammar.y

@@ -578,7 +578,7 @@ type
 
 optional_type
 	: type
-	| type '!'
+	| type '?'
 	;
 
 local_decl_after_type

resources/linux_stack.c3

@@ -3,7 +3,7 @@ import std::io;
 import std::collections::map;
 import std::os;
 
-fn void! test2()
+fn void? test2()
 {
 	builtin::print_backtrace("hello", 1);
 }