Revert to the old demo

code/demo.odin

@@ -1,651 +1,18 @@
 #import "fmt.odin";
-#import "os.odin";
-#import "strconv.odin";
-#import "utf8.odin";
-
-Error :: enum {
-	NONE,
-}
-
-Style_Type :: enum {
-	ITALIC,
-	BOLD,
-	STRIKE,
-}
-
-Node :: union {
-	children:       [dynamic]Node,
-	content:        []byte,
-	inline_content: ^Node,
-	line_number:    int,
-
-	// Block Variants
-	Header{level: int},
-	Document{},
-	Paragraph{},
-	Quote{},
-	Code_Block{language: string},
-	Horizontal_Rule{},
-
-	// Inline Variants
-	Multiple_Inline{},
-	String_Inline{},
-	Soft_Line_Break{},
-	Hard_Line_Break{},
-	Code_Span{},
-	Style{
-		type: Style_Type,
-	}
-}
-
-
-Parser :: struct {
-	data:  []byte,
-	nodes: [dynamic]Node,
-}
-
-parse :: proc(data: []byte) -> ([]Node, Error) {
-	p := Parser{
-		data = data,
-	};
-	err := parse(^p);
-
-	if err != Error.NONE {
-		return nil, err;
-	}
-
-	return p.nodes[..], Error.NONE;
-}
-
-parse :: proc(p: ^Parser) -> Error {
-	is_blank :: proc(line: []byte) -> bool {
-		line = trim_whitespace(line);
-		return len(line) == 0;
-	}
-
-	is_horizontal_rule :: proc(line: []byte) -> bool {
-		char: byte;
-		count := 0;
-		for c, i in line {
-			if c != ' ' && c != '\n' {
-				if c != '-' && c != '_' && c != '*' {
-					return false;
-				}
-				if char == 0 {
-					if i >= 4 {
-						return false;
-					}
-					char = c;
-					count = 1;
-				} else if c == char {
-					count++;
-				} else {
-					return false;
-				}
-			}
-		}
-
-
-		return count >= 3;
-	}
-
-	nodes := make([dynamic]Node);
-
-	line_number: int = 0;
-	prev_was_blank := false;
-	in_code_block := false;
-	code_language := "";
-	code_block_start := 0;
-
-	pos := 0;
-	end := len(p.data);
-	for pos < len(p.data) {
-		line_start := pos;
-		line_end := pos;
-		for p.data[line_end] != '\n' {
-			line_end++;
-		}
-		line := p.data[pos..line_end];
-		pos = line_end+1;
-		line_number++;
-
-		line = tabs_to_spaces_and_append_newline(line);
-		str := cast(string)line;
-
-		skip := in_code_block;
-
-		node: Node;
-		if len(line) > 3 && cast(string)line[..3] == "```" {
-			if !in_code_block {
-				code_block_start = line_start+3;
-				in_code_block = true;
-				code_language = "";
-				rest := trim_whitespace(line[3..]);
-				if len(rest) > 0 {
-					code_language = cast(string)rest;
-				}
-			} else {
-				end := line_start-1;
-				str := p.data[code_block_start..end];
-				node = Node.Code_Block{content = str, language = code_language};
-				in_code_block = false;
-			}
-			skip = true;
-		}
-
-		indent_char := line[indentation(line)];
-		if skip {
-
-		} else if indent_char == '>' {
-			node = Node.Quote{content = line};
-		} else if indent_char == '*' {
-			// fmt.println("List Item");
-		} else if level, content := parse_header(line); level > 0 {
-			node = Node.Header{content = content, level = level};
-		} else if is_horizontal_rule(line) {
-			node = Node.Horizontal_Rule{};
-		} else if !is_blank(line) {
-			node = Node.Paragraph{content = line};
-		}
-
-		if node != nil {
-			node.line_number = line_number;
-			append(nodes, node);
-		}
-	}
-
-
-	for _, i in nodes {
-		using Node;
-		match n in nodes[i] {
-		case Paragraph, Horizontal_Rule, Header, Code_Block:
-			append(p.nodes, nodes[i]);
-		case Quote:
-			// fmt.println("Quote");
-		}
-	}
-
-	for _, i in p.nodes {
-		process_inlines(^p.nodes[i]);
-	}
-
-
-	return Error.NONE;
-}
-
-process_inlines :: proc(node: ^Node) {
-	using Node;
-	match n in node {
-	case Header:
-		n.inline_content = parse_inlines(n.content);
-	case Paragraph:
-		n.inline_content = parse_inlines(trim_right_space(n.content));
-	}
-
-	for _, i in node.children {
-		process_inlines(^node.children[i]);
-	}
-}
-
-Inline_Parser :: struct {
-	data:         []byte,
-	pos:          int,
-	string_start: int,
-	root:         ^Node,
-}
-
-parse_inlines :: proc(data: []byte) -> ^Node {
-	reset_string :: proc(p: ^Inline_Parser) {
-		p.string_start = p.pos;
-	}
-	finalize_string :: proc(p: ^Inline_Parser) {
-		if p.string_start >= p.pos {
-			return;
-		}
-
-
-		str := p.data[p.string_start..p.pos];
-		append(p.root.children, Node.String_Inline{content = trim_right_whitespace(str)});
-	}
-
-	p := Inline_Parser{
-		data = data,
-		root = new(Node),
-	};
-	p.root^ = Node.Multiple_Inline{};
-
-	using Node;
-
-	for p.pos < len(p.data) {
-		node: Node;
-		match p.data[p.pos] {
-		default: p.pos++;
-
-		case '\n':
-			hard_break := false;
-			new_line_pos := p.pos;
-
-			if p.pos >= 2 && p.data[p.pos-1] == ' ' && p.data[p.pos-2] == ' ' {
-				hard_break = true;
-				p.pos -= 2;
-			}
-
-			if p.pos >= 1 && p.data[p.pos-1] == '\\' {
-				hard_break = true;
-				p.pos--;
-			}
-
-
-			for p.pos > 0 && p.data[p.pos-1] == ' ' {
-				p.pos--;
-			}
-			finalize_string(^p);
-
-			if hard_break {
-				node = Hard_Line_Break{};
-			} else {
-				node = Soft_Line_Break{};
-			}
-
-			p.pos = new_line_pos + 1;
-
-			for p.pos < len(p.data) && p.data[p.pos] == ' ' {
-				p.pos++;
-			}
-			reset_string(^p);
-
-		case '`':
-			// "A backtick string is a string of one or more backtick
-			// characters (`) that is neither preceded nor followed by a
-			// backtick."
-			backtick_count: int;
-			for p.pos+backtick_count < len(p.data) && p.data[p.pos+backtick_count] == '`' {
-				backtick_count++;
-			}
-			closing := char_string_index(p.data, '`', p.pos+backtick_count, backtick_count);
-			if closing == -1 {
-				p.pos += backtick_count;
-				break;
-			}
-
-			finalize_string(^p);
-			p.pos += backtick_count;
-
-			content := p.data[p.pos..closing];
-			content = collapse_space(trim_whitespace(content));
-
-			node = Code_Span{content = content};
-
-			p.pos = closing + backtick_count;
-			reset_string(^p);
-
-		case '\\':
-			// "Backslashes before other characters are treated as literal backslashes."
-			if p.pos+1 >= len(p.data) || !is_ascii_punc(p.data[p.pos+1]) {
-				p.pos++;
-				break;
-			}
-			// "Any ASCII punctuation character may be backslash-escaped."
-			finalize_string(^p);
-			p.pos++;
-			node = String_Inline{content = p.data[p.pos..p.pos+1]};
-			p.pos++;
-			reset_string(^p);
-
-		case '&':
-			// "[A]ll valid HTML entities in any context are recognized as such
-			// and converted into unicode characters before they are stored in
-			// the AST."
-			semicolon := -1;
-			for c, i in p.data[p.pos+1..] {
-				if c == ';' {
-					semicolon = i;
-					break;
-				}
-			}
-
-			if semicolon < 0 {
-				p.pos++;
-				break;
-			}
-
-			semicolon += p.pos+1;
-			entity := cast(string)p.data[p.pos+1..semicolon];
-
-			codepoints := make([dynamic]byte, 0, 6);
-
-			if len(entity) > 0 {
-				if entity[0] != '#' {
-					append(codepoints, '&');
-					append(codepoints, ..cast([]byte)entity);
-					append(codepoints, ';');
-				} else {
-					if len(entity) > 1 {
-						base := 10;
-						if entity[1] == 'x' || entity[1] == 'X' {
-							// "Hexadecimal entities consist of &# + either X or x + a
-							// string of 1-8 hexadecimal digits + ;."
-							base = 16;
-						} else {
-							// "Decimal entities consist of &# + a string of 1–8 arabic
-							// digits + ;. Again, these entities need to be recognised and
-							// tranformed into their corresponding UTF8 codepoints. Invalid
-							// Unicode codepoints will be written as the “unknown
-							// codepoint” character (0xFFFD)."
-						}
-						codepoint := strconv.parse_uint(entity[2..], base);
-						data, len := utf8.encode_rune(cast(rune)codepoint);
-						append(codepoints, ..data[..len]);
-					}
-				}
-			}
-
-			if len(codepoints) == 0 {
-				p.pos++;
-				break;
-			}
-
-			finalize_string(^p);
-			node = String_Inline{content = codepoints[..]};
-			p.pos = semicolon+1;
-			reset_string(^p);
-		}
-
-		if node != nil {
-			append(p.root.children, node);
-		}
-	}
-
-	finalize_string(^p);
-
-	return p.root;
-}
-
-is_ascii_punc :: proc(char: byte) -> bool {
-	match char {
-	case '!', '"', '#', '$', '%',
-	     '&', '\'', '(', ')',
-	     '*', '+', ',', '-',
-	     '.', '/', ':', ';',
-	     '<', '=', '>', '?', '@', '[', '\\', ']',
-	     '^', '_', '`', '{', '|', '}', '~':
-		return true;
-	}
-	return false;
-}
-
-char_string_index :: proc(data: []byte, char: byte, start, length: int) -> int {
-	count: int;
-	for i in start..len(data) {
-		if data[i] == char {
-			count++;
-			if count == length {
-				if i+1 >= len(data) || data[i+1] != char {
-					return i+1 - count;
-				}
-			}
-		} else {
-			count = 0;
-		}
-	}
-	return -1;
-}
-
-collapse_space :: proc(data: []byte) -> []byte {
-	out := make([]byte, 0, len(data));
-	prev_was_space := false;
-	for c in data {
-		if c == ' ' || c == '\n' {
-			if !prev_was_space {
-				append(out, ' ');
-				prev_was_space = true;
-			}
-		} else {
-			append(out, c);
-			prev_was_space = false;
-		}
-	}
-
-	return out;
-}
-
-
-parse_header :: proc(line: []byte) -> (int, []byte) {
-	// "The opening # character may be indented 0-3 spaces."
-	indent := indentation(line);
-	if indent > 3 {
-		return -1, nil;
-	}
-	line = line[indent..];
-
-	// "The header level is equal to the number of # characters in the opening sequence."
-	level := 0;
-	for c, i in line {
-		if c != '#' {
-			level = i;
-			break;
-		}
-	}
-
-	if level < 1 || level > 6 {
-		return -1, nil;
-	}
-	line = line[level..];
-	// "The opening sequence of # characters cannot be followed directly by a
-	// nonspace character."
-	if line[0] != ' ' && line[0] != '\n' {
-		return -1, nil;
-	}
-	// "The optional closing sequence of #s [...] may be followed by spaces
-	// only."
-
-	trailer_start := len(line) - 1;
-	for trailer_start > 0 && line[trailer_start-1] == ' ' {
-		trailer_start--;
-	}
-	for trailer_start > 0 && line[trailer_start-1] == '#' {
-		trailer_start--;
-	}
-	// "The optional closing sequence of #s must be preceded by a space [...]."
-	// Note that (if the header is empty) this may be the same space as after
-	// the opening sequence.
-	if trailer_start > 0 && line[trailer_start-1] == ' ' {
-		line = line[..trailer_start];
-	}
-
-	// "The raw contents of the header are stripped of leading and trailing
-	// spaces before being parsed as inline content."
-	line = trim_space(line);
-	return level, line;
-
-}
-
-indentation :: proc(line: []byte) -> int {
-	for c, i in line {
-		if c != ' ' {
-			return i;
-		}
-	}
-	panic("indentation() expects line to end in newline character");
-	return 0;
-}
-
-
-TAB_STOP :: 4;
-
-tabs_to_spaces_and_append_newline :: proc(line: []byte) -> []byte {
-	tab_count: int;
-	for c in line {
-		if c == '\t' {
-			tab_count++;
-		}
-	}
-
-	out := make([]byte, 0, len(line) + tab_count*(TAB_STOP-1) + 1);
-
-	rune_count: int;
-	for r in cast(string)line {
-		if r == '\t' {
-			spaces_count := TAB_STOP - rune_count%TAB_STOP;
-			for i in 0..spaces_count {
-				append(out, ' ');
-			}
-			rune_count += spaces_count;
-		} else {
-			match r {
-			case '\r', '\v', '\f':
-				append(out, ' ');
-			default:
-				c, l := utf8.encode_rune(r);
-				append(out, ..c[0..l]);
-			}
-			rune_count++;
-		}
-	}
-	append(out, '\n');
-	return out;
-}
-
-trim_right_whitespace :: proc(data: []byte) -> []byte {
-	c := data;
-	for i := len(c)-1; i >= 0; i-- {
-		match c[i] {
-		case ' ', '\t', '\v', '\f', '\r', '\n':
-			c = c[..i];
-			continue;
-		}
-		break;
-	}
-
-	return c;
-}
-
-
-trim_right_space :: proc(data: []byte) -> []byte {
-	c := data;
-	for i := len(c)-1; i >= 0; i-- {
-		if c[i] != ' ' {
-			break;
-		}
-		c = c[..i];
-	}
-
-	return c;
-}
-
-trim_whitespace :: proc(data: []byte) -> []byte {
-	data = trim_right_whitespace(data);
-	index := 0;
-	for c in data {
-		match c {
-		case ' ', '\t', '\v', '\f', '\r':
-			index++;
-			continue;
-		}
-		break;
-	}
-	return data[index..];
-}
-
-trim_space :: proc(data: []byte) -> []byte {
-	index := 0;
-	for c in data {
-		if c != ' ' {
-			break;
-		}
-		index++;
-	}
-	data = data[index..];
-
-	for i := len(data)-1; i >= 0; i-- {
-		if data[i] != ' ' {
-			break;
-		}
-		data = data[..i];
-	}
-
-	return data;
-}
-
-escape_map := map[byte]string{
-	'"' = "&quot;",
-	'&' = "&amp;",
-	'<' = "&lt;",
-	'>' = "&gt;",
-};
-
 
 main :: proc() {
-	data, ok := os.read_entire_file("W:/Odin/misc/markdown_test.md");
-	if !ok {
-		fmt.println("Failure to load file");
-		return;
-	}
-
-	nodes, err := parse(data);
-	if err != Error.NONE {
-		fmt.println("Failure to parse file");
-		return;
-	}
-
-	write_espaced :: proc(data: []byte) {
-		start: int;
-		for c, i in data {
-			if escaped, ok := escape_map[c]; ok {
-				fmt.print(cast(string)data[start..i]);
-				fmt.print(escaped);
-				start = i+1;
-			}
-		}
-		fmt.print(cast(string)data[start..]);
-	}
+	immutable program := "+ + * - /";
+	accumulator := 0;
 
-	print_inline_as_html :: proc(node: ^Node) {
-		using Node;
-		match n in node {
-		case Multiple_Inline:
-			for _, i in n.children {
-				print_inline_as_html(^n.children[i]);
-			}
-		case String_Inline:
-			write_espaced(n.content);
-		case Soft_Line_Break:
-			// fmt.println();
-		case Hard_Line_Break:
-			fmt.println("<br>");
-		case Code_Span:
-			fmt.print("<code>");
-			write_espaced(n.content);
-			fmt.print("</code>");
+	for token in program {
+		match token {
+		case '+': accumulator += 1;
+		case '-': accumulator -= 1;
+		case '*': accumulator *= 2;
+		case '/': accumulator /= 2;
+		default: // Ignore everything else
 		}
 	}
 
-	print_node_as_html :: proc(node: ^Node) {
-		using Node;
-		match n in node {
-		case Header:
-			fmt.printf("<h%d>", n.level);
-			print_inline_as_html(n.inline_content);
-			fmt.printf("</h%d>\n", n.level);
-		case Paragraph:
-			fmt.print("<p>");
-			print_inline_as_html(n.inline_content);
-			fmt.println("</p>");
-		case Horizontal_Rule:
-			fmt.println("<hr>");
-		case Code_Block:
-			if n.language != "" {
-				fmt.printf("<pre><code class=\"language-%s\">", n.language);
-			} else {
-				fmt.print("<pre><code>");
-			}
-			fmt.print(cast(string)n.content);
-			fmt.println("</code></pre>");
-		case Quote:
-		}
-	}
-
-	for _, i in nodes {
-		print_node_as_html(^nodes[i]);
-	}
+	fmt.printf("The program \"%s\" calculates the value %d\n", program, accumulator);
 }