fix quit event to exit game loop

.gitignore

@@ -1,2 +1,3 @@
 target/
+SDL2*.dll
 

bong_grammar.txt

@@ -11,8 +11,7 @@ element_fields -> (_ element_field (__linebreak__ element_field):*):? __linebrea
 
 element_field ->
     | element
-    | Id
-    | Class
+    | specifier_chain
     | element_property
     | value
 
@@ -20,22 +19,20 @@ element_property -> Name _ ("=" | ":") _ value
 
 single_line_fields ->
     (first_single_line_field
-        (__singleline__ single_line_field):*):? _singleline_
+        (__sl__ single_line_field):*):? _sl_
 
 first_single_line_field ->
-    | Id
-    | Class
-    | __singleline__ single_line_element_property
-    | __singleline__ single_line_value
+    | specifier_chain
+    | __sl__ single_line_element_property
+    | __sl__ single_line_value
 
 single_line_field ->
-    | Id
-    | Class
+    | specifier_chain
     | single_line_element_property
     | single_line_value
 
 single_line_element_property ->
-    Name _singleline_ ("=" | ":") _singleline_ value
+    Name _sl_ ("=" | ":") _sl_ value
 
 single_line_value ->
     | array
@@ -45,6 +42,12 @@ single_line_value ->
     | bool
     | Null
 
+specifier_chain -> specifier:+
+
+specifier ->
+    | Id
+    | Class
+
 value ->
     | object
     | array
@@ -56,7 +59,8 @@ value ->
 
 object -> "{" object_properties "}"
 
-object_properties -> (_ object_property (_ "," _ object_property):* _ ",":?):? _
+object_properties ->
+    (_ object_property (_ "," _ object_property):* _ ",":?):? _
 
 object_property -> (Name | String) _ ("=" | ":") _ value
 
@@ -66,28 +70,27 @@ array_values -> (_ value (_ "," _ value):* _ ",":?):? _
 
 bool -> True | False
 
-__singleline__ -> mandatory_same_line_whitespace
-_singleline_ -> optional_same_line_whitespace
 __linebreak__ -> mandatory_linebreak
-__ -> mandatory_whitespace
+__sl__ -> mandatory_single_line_whitespace
+_sl_ -> optional_single_line_whitespace
+__ml__ -> mandatory_whitespace
 _ -> optional_whitespace
 
-mandatory_same_line_whitespace -> single_line_whitespace:+
-optional_same_line_whitespace -> single_line_whitespace:*
-
 mandatory_linebreak ->
     single_line_whitespace:*
     line_breaker
     whitespace_and_line_break:*
 
-single_line_whitespace -> SingleLineWhitespace | MultiLineComment
-
 line_breaker -> MultiLineComment | MultiLineWhitespace | ";"
 
 whitespace_and_line_break -> singular_whitespace | ";"
 
-optional_whitespace -> singular_whitespace:*
+mandatory_single_line_whitespace -> single_line_whitespace:+
+optional_single_line_whitespace -> single_line_whitespace:*
 
+single_line_whitespace -> SingleLineWhitespace | MultiLineComment
+
+optional_whitespace -> singular_whitespace:*
 mandatory_whitespace -> singular_whitespace:+
 
 singular_whitespace ->

src/bong/lexer.rs

@@ -1,17 +1,17 @@
-#[derive(Debug, Clone, PartialEq, Eq)]
+#[derive(Debug, Clone, PartialEq)]
 pub enum ErrorType {
     UnexpectedToken(char),
     InvalidConstructor,
 }
 
-#[derive(Debug, Clone, PartialEq, Eq)]
+#[derive(Debug, Clone, PartialEq)]
 pub struct Error {
     error: ErrorType,
     line: isize,
     col: isize,
 }
 
-#[derive(Debug, Clone, PartialEq, Eq)]
+#[derive(Debug, Clone, PartialEq)]
 pub enum Token {
     Name(String),
     Id(String),
@@ -30,10 +30,10 @@ pub enum Token {
     RBrace(String),
     LBracket(String),
     RBracket(String),
-    Equal(String),
-    Colon(String),
-    SemiColon(String),
-    Comma(String),
+    Equal(String),     // not implemented
+    Colon(String),     // not implemented
+    SemiColon(String), // not implemented
+    Comma(String),     // not implemented
 }
 
 #[derive(PartialEq)]

src/bong/parser.rs

@@ -27,6 +27,13 @@ pub struct Parser {
 
 type ParserError = String;
 
+enum ElementField {
+    Id(String),
+    Class(String),
+    Property(Box<Node>),
+    Value(Node),
+}
+
 impl Parser {
     pub fn new(tokens: Vec<Token>) -> Self {
         Self { tokens, index: 0 }
@@ -41,23 +48,63 @@ impl Parser {
     }
 
     fn parse_element(&mut self) -> Result<Node, ParserError> {
+        let name = match self.current() {
+            Some(Token::Name(value)) => value.clone(),
+            _ => panic!("checked by previous predicate"),
+        };
+        self.step();
         todo!()
     }
 
+    fn parse_singe_line_fields(&mut self) -> Result<Vec<ElementField>, ParserError> {
+        let mut fields = Vec::<ElementField>::new();
+        match self.current() {
+            Some(Token::Id(value)) => {
+                fields.push(ElementField::Id(value.clone()));
+                self.step();
+                todo!()
+            }
+            Some(Token::Class(value)) => {
+                fields.push(ElementField::Class(value.clone()));
+                self.step();
+                todo!()
+            }
+            Some(_) => todo!(),
+            _ => Ok(fields),
+        }
+    }
+
     fn parse_value(&mut self) -> Result<Node, ParserError> {
         match self.current() {
             Some(Token::LBrace(_)) => self.parse_object(),
             Some(Token::LBracket(_)) => self.parse_object(),
-            Some(Token::Int(value)) => Ok(Node::Int(
-                value.parse().map_err(|_| "malformed int".to_string())?,
-            )),
-            Some(Token::Float(value)) => Ok(Node::Int(
-                value.parse().map_err(|_| "malformed float".to_string())?,
-            )),
-            Some(Token::String(value)) => Ok(Node::String(value[1..value.len() - 1].to_string())),
-            Some(Token::False(_)) => Ok(Node::Bool(false)),
-            Some(Token::True(_)) => Ok(Node::Bool(false)),
-            Some(Token::Null(_)) => Ok(Node::Null),
+            Some(Token::Int(value)) => {
+                let value = value.parse().map_err(|_| "malformed int".to_string())?;
+                self.step();
+                Ok(Node::Int(value))
+            }
+            Some(Token::Float(value)) => {
+                let value = value.parse().map_err(|_| "malformed float".to_string())?;
+                self.step();
+                Ok(Node::Float(value))
+            }
+            Some(Token::String(value)) => {
+                let value = value[1..value.len() - 1].to_string();
+                self.step();
+                Ok(Node::String(value))
+            }
+            Some(Token::False(_)) => {
+                self.step();
+                Ok(Node::Bool(false))
+            }
+            Some(Token::True(_)) => {
+                self.step();
+                Ok(Node::Bool(false))
+            }
+            Some(Token::Null(_)) => {
+                self.step();
+                Ok(Node::Null)
+            }
             Some(_) => Err("unexpected token, expected value".to_owned()),
             None => Err("expected value".to_owned()),
         }
@@ -65,6 +112,8 @@ impl Parser {
 
     fn parse_object(&mut self) -> Result<Node, ParserError> {
         self.step();
+        // object_properties -> (_ (...)):? _ <=> object_properties -> _ | _ (...) _
+        self.parse_optional_whitespace()?;
         let mut values = HashMap::<String, Box<Node>>::new();
         match self.current() {
             Some(Token::RBrace(_)) => {
@@ -72,27 +121,32 @@ impl Parser {
                 Ok(Node::Object(values))
             }
             Some(t @ (Token::Name(_) | Token::String(_))) => {
-                // let key = match t {
-                //     Token::Name(v) => v,
-                //     Token::String(v) => &v[1..v.len() - 1].to_string(),
-                //     _ => panic!("checked by previous predicate"),
-                // };
-                // self.step();
-                // match self.current() {
-                //     Some(Token::Equal(_) | Token::Colon(_)) => {}
-                //     _ => return Err("expected ':' or '='".to_string()),
-                // }
-                // self.step();
-                // values[key] = Box::new(self.parse_value()?);
-                // self.parse_object_tail(values)
-                todo!()
+                let key = match t {
+                    Token::Name(v) => v.clone(),
+                    Token::String(v) => v[1..v.len() - 1].to_string(),
+                    _ => panic!("checked by previous predicate"),
+                };
+                self.step();
+                self.parse_optional_whitespace()?;
+                match self.current() {
+                    Some(Token::Equal(_) | Token::Colon(_)) => {}
+                    _ => return Err("expected ':' or '='".to_string()),
+                }
+                self.step();
+                self.parse_optional_whitespace()?;
+                values.insert(key, Box::new(self.parse_value()?));
+                self.parse_object_tail(values)
             }
             _ => Err("expected Name, String or '}'".to_string()),
         }
     }
 
-    fn parse_object_tail(&mut self, values: HashMap<String, Box<Node>>) -> Result<Node, String> {
+    fn parse_object_tail(
+        &mut self,
+        mut values: HashMap<String, Box<Node>>,
+    ) -> Result<Node, String> {
         loop {
+            self.parse_optional_whitespace()?;
             match self.current() {
                 Some(Token::RBrace(_)) => {
                     self.step();
@@ -100,25 +154,28 @@ impl Parser {
                 }
                 Some(Token::Comma(_)) => {
                     self.step();
+                    self.parse_optional_whitespace()?;
                     match self.current() {
                         Some(Token::RBrace(_)) => {
                             self.step();
                             break Ok(Node::Object(values));
                         }
                         Some(t @ (Token::Name(_) | Token::String(_))) => {
-                            // let key = match t {
-                            //     Token::Name(v) => v,
-                            //     Token::String(v) => &v[1..v.len() - 1].to_string(),
-                            //     _ => panic!("unterminated object, checked by previous predicate"),
-                            // };
-                            // self.step();
-                            // match self.current() {
-                            //     Some(Token::Equal(_) | Token::Colon(_)) => {}
-                            //     _ => return Err("expected ':' or '='".to_string()),
-                            // }
-                            // self.step();
-                            // values[key] = Box::new(self.parse_value()?);
-                            todo!()
+                            let key = match t {
+                                Token::Name(v) => v.clone(),
+                                Token::String(v) => v[1..v.len() - 1].to_string(),
+                                _ => panic!("unterminated object, checked by previous predicate"),
+                            };
+                            self.step();
+                            self.parse_optional_whitespace()?;
+                            match self.current() {
+                                Some(Token::Equal(_) | Token::Colon(_)) => {}
+                                _ => return Err("expected ':' or '='".to_string()),
+                            }
+                            self.step();
+                            self.parse_optional_whitespace()?;
+                            values.insert(key, Box::new(self.parse_value()?));
+                            self.parse_optional_whitespace()?;
                         }
                         _ => {
                             break Err(
@@ -134,6 +191,7 @@ impl Parser {
 
     fn parse_array(&mut self) -> Result<Node, ParserError> {
         self.step();
+        self.parse_optional_whitespace()?;
         let mut values = Vec::<Node>::new();
         match self.current() {
             Some(Token::RBracket(_)) => {
@@ -142,12 +200,112 @@ impl Parser {
             }
             Some(_) => {
                 values.push(self.parse_value()?);
-                todo!()
+                loop {
+                    match self.current() {
+                        Some(Token::RBracket(_)) => {
+                            self.step();
+                            break Ok(Node::Array(values));
+                        }
+                        Some(Token::Comma(_)) => {
+                            self.step();
+                            self.parse_optional_whitespace()?;
+                            match self.current() {
+                                Some(Token::RBracket(_)) => {
+                                    self.step();
+                                    self.parse_optional_whitespace()?;
+                                    break Ok(Node::Array(values));
+                                }
+                                _ => {
+                                    self.step();
+                                    self.parse_optional_whitespace()?;
+                                    values.push(self.parse_value()?)
+                                }
+                            }
+                        }
+                        _ => break Err("unterminated array, expected Value or ']'".to_string()),
+                    }
+                }
             }
             _ => Err("unterminated array, expected Value or ']'".to_string()),
         }
     }
 
+    fn parse_mandatory_linebreak(&mut self) -> Result<(), ParserError> {
+        self.parse_single_line_optional_whitespace()?;
+        match self.current() {
+            Some(Token::MlWhitespace(_) | Token::MlComment(_) | Token::SemiColon(_)) => {
+                self.step();
+                loop {
+                    match self.current() {
+                        Some(
+                            Token::MlWhitespace(_)
+                            | Token::SlWhitespace(_)
+                            | Token::MlComment(_)
+                            | Token::SlComment(_)
+                            | Token::SemiColon(_),
+                        ) => {
+                            self.step();
+                        }
+                        _ => break Ok(()),
+                    }
+                }
+            }
+            _ => Err("expected linebreak".to_string()),
+        }
+    }
+
+    fn parse_single_line_mandatory_whitespace(&mut self) -> Result<(), ParserError> {
+        match self.current() {
+            Some(Token::SlWhitespace(_) | Token::SlComment(_)) => {
+                self.step();
+                self.parse_single_line_optional_whitespace()
+            }
+            _ => Err("expected whitespace".to_string()),
+        }
+    }
+
+    fn parse_single_line_optional_whitespace(&mut self) -> Result<(), ParserError> {
+        loop {
+            match self.current() {
+                Some(Token::SlWhitespace(_) | Token::SlComment(_)) => {
+                    self.step();
+                }
+                _ => break Ok(()),
+            }
+        }
+    }
+
+    fn parse_mandatory_whitespace(&mut self) -> Result<(), ParserError> {
+        match self.current() {
+            Some(
+                Token::MlWhitespace(_)
+                | Token::SlWhitespace(_)
+                | Token::MlComment(_)
+                | Token::SlComment(_),
+            ) => {
+                self.step();
+                self.parse_optional_whitespace()
+            }
+            _ => Err("expected whitespace".to_string()),
+        }
+    }
+
+    fn parse_optional_whitespace(&mut self) -> Result<(), ParserError> {
+        loop {
+            match self.current() {
+                Some(
+                    Token::MlWhitespace(_)
+                    | Token::SlWhitespace(_)
+                    | Token::MlComment(_)
+                    | Token::SlComment(_),
+                ) => {
+                    self.step();
+                }
+                _ => break Ok(()),
+            }
+        }
+    }
+
     fn step(&mut self) {
         self.index += 1
     }

src/main.rs

@@ -1,9 +1,28 @@
 use std::time::Duration;
 
-use sdl2::{event::Event, keyboard::Keycode, pixels::Color};
+use sdl2::{
+    event::Event, keyboard::Keycode, pixels::Color, rect::Rect, render::Canvas, video::Window,
+};
 
 mod bong;
 
+enum Element {
+    Div(Vec<Element>),
+    Rectangle(Color),
+}
+
+impl Element {
+    fn render(&self, canvas: &mut Canvas<Window>, x: i32, y: i32) {
+        match self {
+            Element::Div(_) => todo!(),
+            Element::Rectangle(color) => {
+                canvas.set_draw_color(*color);
+                let _ = canvas.fill_rect(Rect::new(x, y, 50, 50));
+            }
+        }
+    }
+}
+
 fn main() {
     let sdl_context = sdl2::init().unwrap();
     let video_subsystem = sdl_context.video().unwrap();
@@ -20,10 +39,8 @@ fn main() {
     canvas.clear();
     canvas.present();
     let mut event_pump = sdl_context.event_pump().unwrap();
-    let mut i = 0;
-    'running: loop {
-        i = (i + 1) % 255;
-        canvas.set_draw_color(Color::RGB(i, 64, 255 - i));
+    'game_loop: loop {
+        canvas.set_draw_color(Color::RGB(170, 200, 255));
         canvas.clear();
         for event in event_pump.poll_iter() {
             match event {
@@ -31,11 +48,18 @@ fn main() {
                 | Event::KeyDown {
                     keycode: Some(Keycode::Escape),
                     ..
-                } => break 'running,
+                } => break 'game_loop,
                 _ => {}
             }
         }
         // The rest of the game loop goes here...
+        let dom = Element::Div(vec![
+            Element::Rectangle(Color::RGB(1, 238, 34)),
+            Element::Rectangle(Color::RGB(123, 123, 123)),
+        ]);
+
+        canvas.set_draw_color(Color::RGB(255, 0, 0));
+        let _ = canvas.fill_rect(Rect::new(0, 0, 50, 50));
 
         canvas.present();
         ::std::thread::sleep(Duration::new(0, 1_000_000_000u32 / 60));