Majority of untested implementation of Statement; Some changes to parser structure and code style; Added .gitignore

.gitignore

@@ -0,0 +1 @@
+target

src/lang.rs

@@ -1,4 +1,4 @@
-#[derive(Debug, Clone)]
+#[derive(Clone)]
 struct Reader<'a> {
     slice: &'a str,
     full: &'a str,
@@ -8,13 +8,16 @@ struct Reader<'a> {
 struct Error(String);
 
 impl Error {
-  fn new<T>(message: &str, reader: &Reader) -> Result<T,Error> {
+    fn new<T>(message: &str, _reader: &Reader) -> Result<T, Error> {
         Err(Error(message.to_string()))
     }
 }
 
+type Comment = String;
+
 #[derive(Debug)]
 struct Piece<T> {
+    comment: Comment,
     index: usize,
     width: usize,
     it: T,
@@ -25,21 +28,24 @@ impl<T> Piece<T> {
         Piece {
             it,
             index: reader.slice.as_ptr() as usize - reader.full.as_ptr() as usize,
-      width
+            width,
+            comment: String::new()
         }
     }
     fn from<A, B>(it: T, begin: &Piece<A>, end: &Piece<B>) -> Piece<T> {
         Piece {
             it,
             index: begin.index,
-      width: end.index + end.width - begin.index
+            width: end.index + end.width - begin.index,
+            comment: String::new()
         }
     }
     fn null(&self) -> Piece<()> {
         Piece {
             it: (),
             index: self.index,
-      width: self.width
+            width: self.width,
+            comment: String::new()
         }
     }
 }
@@ -51,33 +57,40 @@ impl<'a> From<&'a str> for Reader<'a> {
     fn from(str: &'a str) -> Self {
         Reader {
             full: str,
-      slice: str
+            slice: str,
         }
     }
 }
 
 impl<'a> Reader<'a> {
-  fn trim(&mut self) -> Result<&Self,Error> {
+    fn trim(&mut self) -> Result<Comment, Error> {
         self.slice = self.slice.trim_start();
         if self.slice.starts_with("--") {
-      if self.slice[2..].starts_with("[[") {
+            let comment = if self.slice[2..].starts_with("[[") {
                 match self.slice.find("]]") {
                     Some(i) => {
+                        let comment = &self.slice[4..i + 2];
                         self.slice = &self.slice[i + 2..].trim();
-            Ok(self)
+                        Ok(comment)
-          }
-          _ => {
-            self.error("Unterminated multi-line comment")
                     }
+                    _ => self.error("Unterminated multi-line comment"),
                 }
             } else {
+                let comment;
                 if let Some(i) = self.slice.find("\n") {
                     self.slice = &self.slice[i + 1..].trim();
-        }
+                    comment = &self.slice[2..i+1];
-        Ok(self)
-      }
                 } else {
-      Ok(self)
+                    self.slice = &self.slice[..self.slice.len() - 1];
+                    comment = &self.slice[2..];
+                }
+                Ok(comment)
+            }?;
+            self.trim().map(|it| {
+                it + comment
+            })
+        } else {
+            Ok(String::new())
         }
     }
     fn consume(&mut self, start: &str) -> Result<&Self, Error> {
@@ -89,7 +102,10 @@ impl<'a> Reader<'a> {
             self.error(format!("Expected '{}'", start).as_str())
         }
     }
-  fn take<T>(&mut self) -> Result<Piece<T>,Error> where T: Parse {
+    fn take<T>(&mut self) -> Result<Piece<T>, Error>
+    where
+        T: Parse,
+    {
         self.trim()?;
         T::consume(self)
     }
@@ -111,12 +127,13 @@ struct Name(String);
 // - The reader may have not been trimmed
 trait Parse {
     fn consume(reader: &mut Reader) -> Result<Piece<Self>, Error>
-  where Self: Sized;
+    where
+        Self: Sized;
 }
 impl Parse for Name {
     fn consume(reader: &mut Reader) -> Result<Piece<Self>, Error>
     where
-    Self: Sized
+        Self: Sized,
     {
         reader.trim()?;
         let mut chars = reader.slice.chars();
@@ -127,12 +144,18 @@ impl Parse for Name {
             }
             Some(c) => {
                 if !(c.is_alphabetic() || c == '_') {
-          return reader.error("Identifier must begin with alphabetic character")
+                    return reader.error("Identifier must begin with alphabetic character");
                 }
             }
         };
-    end += chars.take_while(|c| { c.is_alphanumeric() || *c == '_' }).count();
+        end += chars
-    let result = Ok(Piece::of(Name(reader.slice[..end].to_string()),reader,end));
+            .take_while(|c| c.is_alphanumeric() || *c == '_')
+            .count();
+        let result = Ok(Piece::of(
+            Name(reader.slice[..end].to_string()),
+            reader,
+            end,
+        ));
         reader.slice = &reader.slice[end..];
         result
     }
@@ -140,21 +163,35 @@ impl Parse for Name {
 impl Parse for Number {
     fn consume(reader: &mut Reader) -> Result<Piece<Number>, Error>
     where
-    Self: Sized
+        Self: Sized,
     {
         reader.trim()?;
         let mut end;
         if reader.slice.starts_with("0x") {
-      end = reader.slice[2..].chars().take_while(|c| c.is_digit(16)).count()+2;
+            end = reader.slice[2..]
-      if end == 2 { end = 0 }
+                .chars()
+                .take_while(|c| c.is_digit(16))
+                .count()
+                + 2;
+            if end == 2 {
+                end = 0
+            }
         } else {
-      end = reader.slice.chars().take_while(|c| c.is_digit(10) || *c == '.').count();
+            end = reader
+                .slice
+                .chars()
+                .take_while(|c| c.is_digit(10) || *c == '.')
+                .count();
         }
         if end == 0 {
             reader.error("Could not parse number".into())
         } else {
             reader.slice = &reader.slice[end..];
-      Ok(Piece::of(Number(reader.slice[..end].to_string()),reader,end))
+            Ok(Piece::of(
+                Number(reader.slice[..end].to_string()),
+                reader,
+                end,
+            ))
         }
     }
 }
@@ -173,7 +210,7 @@ impl Parse for String {
             Some('"') => {
                 term1 = '"';
                 term2 = None;
-      },
+            }
             Some('\'') => {
                 term1 = '\'';
                 term2 = None;
@@ -190,10 +227,8 @@ impl Parse for String {
             match chars.next() {
                 Some(c) => {
                     match c {
-            '\\' => {
+                        '\\' => match chars.next() {
-              match chars.next() {
+                            Some(c) => match c {
-                Some(c) => {
-                  match c {
                                 'n' => string.push('\n'),
                                 'r' => string.push('\r'),
                                 't' => string.push('\t'),
@@ -203,21 +238,21 @@ impl Parse for String {
                                 it => {
                                     string.push(it);
                                 }
-                  }
+                            },
-                }
                             None => {}
-              }
+                        },
-            }
                         '\r' => {} // todo: ?
                         '\n' if term2.is_none() => {
                             return reader.error("Found newline while parsing string");
                         }
                         term if term == term1 => {
                             // If the second terminator exists and is the next char, or there is no second terminator
-              if !term2.is_some() || chars.next().is_some_and(|it| it == term2.unwrap()) {
+                            if !term2.is_some()
+                                || chars.next().is_some_and(|it| it == term2.unwrap())
+                            {
                                 let length = string.len();
                                 reader.slice = &reader.slice[length..];
-                return Ok(Piece::of(string,reader,length))
+                                return Ok(Piece::of(string, reader, length));
                             // There is a second terminator and it wasn't the next char
                             } else {
                                 string.push(term)
@@ -238,7 +273,7 @@ impl Parse for String {
 
 // AST
 #[derive(Debug)]
-struct Block(Vec<Piece<Statement>>);
+struct Block(Vec<Piece<Statement>>, Vec<Piece<Expression>>);
 #[derive(Debug)]
 enum Statement {
     Semicolon,
@@ -247,22 +282,27 @@ enum Statement {
     Label(Piece<Name>),
     Break,
     Continue,
-  Return(Vec<Piece<Expression>>),
     Goto(Piece<Name>),
     Do(Block),
     While(Piece<Expression>, Block),
     Repeat(Block, Piece<Expression>),
     If(Vec<Piece<Expression>>, Vec<Block>, Option<Block>),
-  Range(Piece<Name>,Piece<Expression>,Piece<Expression>,Option<Piece<Expression>>,Block),
+    Range(
+        Piece<Name>,
+        Piece<Expression>,
+        Piece<Expression>,
+        Option<Piece<Expression>>,
+        Block,
+    ),
     Iterator(Vec<Piece<Name>>, Vec<Piece<Expression>>, Block),
     Function(Vec<Piece<Name>>, Option<Piece<Name>>, Function),
     LocalFunction(Piece<Name>, Function),
-  Declaration(Vec<Piece<Name>>,Vec<Piece<Expression>>)
+    Declaration(Vec<Piece<Name>>, Vec<Piece<Expression>>),
 }
 #[derive(Debug)]
 enum Variable {
     Name(Name),
-  Index(Box<Prefix>,Box<Expression>)
+    Index(Box<Prefix>, Box<Expression>),
 }
 #[derive(Debug)]
 enum Expression {
@@ -276,7 +316,7 @@ enum Expression {
     Prefix(Box<Prefix>),
     Table(Vec<Field>),
     Binary(Box<Expression>, BinaryOp, Box<Expression>),
-  Unary(UnaryOp,Box<Expression>)
+    Unary(UnaryOp, Box<Expression>),
 }
 #[derive(Debug)]
 enum Prefix {
@@ -295,7 +335,7 @@ struct Field(Option<Expression>,Expression);
 #[derive(Debug)]
 enum FieldSep {
     Comma,
-  Semicolon
+    Semicolon,
 }
 #[derive(Debug)]
 enum BinaryOp {
@@ -319,14 +359,14 @@ enum BinaryOp {
     Equivalent,
     NotEqual,
     And,
-  Or
+    Or,
 }
 #[derive(Debug)]
 enum UnaryOp {
     Negate,
     Not,
     Ampersand,
-  Tilde
+    Tilde,
 }
 
 impl<T: Parse> Parse for Vec<Piece<T>> {
@@ -334,13 +374,14 @@ impl<T: Parse> Parse for Vec<Piece<T>> {
     where
         Self: Sized,
     {
-    let result: Vec<Piece<T>> = Vec::new();
+        let mut result: Vec<Piece<T>> = Vec::new();
         reader.trim()?;
         loop {
             if let Ok(it) = reader.take::<T>() {
+                result.push(it);
                 reader.trim()?;
                 if !reader.consume(",").is_ok() {
-          break
+                    break;
                 }
             }
         }
@@ -361,25 +402,25 @@ impl Parse for Function {
         let mut parameters: Vec<Piece<Name>> = Vec::new();
         let mut vararg = None;
         loop {
-      reader.trim()?;
             if let Ok(name) = reader.take::<Name>() {
                 parameters.push(name);
-        reader.trim()?;
                 if vararg.is_some() {
-          return reader.error("Unexpected argument after vararg '...'")
+                    return reader.error("Unexpected argument after vararg '...'");
                 }
                 if !reader.consume(",").is_ok() {
-          break
+                    break;
                 }
             }
             vararg = reader.take::<VarArg>().ok()
         }
-    reader.trim()?;
         reader.consume(")")?;
-    reader.trim()?;
         let end = reader.marker();
         let block = reader.take::<Block>()?;
-    Ok(Piece::from(Function(parameters,vararg,block),&start,&end))
+        Ok(Piece::from(
+            Function(parameters, vararg, block),
+            &start,
+            &end,
+        ))
     }
 }
 
@@ -395,173 +436,213 @@ impl Parse for VarArg {
             Ok(Piece::from(VarArg(Some(name.it)), &start, &end))
         } else {
             end = reader.marker();
-      Ok(Piece::from(VarArg(name.map(|piece| piece.it)), &start, &end))
+            Ok(Piece::from(
+                VarArg(name.map(|piece| piece.it)),
+                &start,
+                &end,
+            ))
         }
     }
 }
 
 impl Parse for Expression {
+    fn consume(reader: &mut Reader) -> Result<Piece<Self>, Error> {
+        reader.trim()?;
+        
+    }
+}
+
+impl Parse for Call {
     fn consume(reader: &mut Reader) -> Result<Piece<Self>, Error> {
         
     }
 }
 
-// todo: WHY am i trimming everywhere... fix ts; its handled in take and consume already, comments can be stored in piece
 impl Parse for Statement {
-  fn consume(mut reader: &mut Reader) -> Result<Piece<Statement>, Error> {
+    fn consume(initial: &mut Reader) -> Result<Piece<Statement>, Error> {
-    reader.trim()?;
+        initial.trim()?;
-    let start = reader.marker();
+        let start = initial.marker();
-    let restore = |new: &mut Reader| {
+        // todo: it is safer to pass back the new reader in the Ok, and then map it out
-      reader = new
+        if initial.consume("break").is_ok() {
-    };
+            Ok(Piece::from(Statement::Break, &start, &initial.marker()))
-    if reader.consume("break").is_ok() {
+        } else if initial.consume("continue").is_ok() {
-      Ok(Piece::from(Statement::Break,&start,&reader.marker()))
+            Ok(Piece::from(Statement::Continue, &start, &initial.marker()))
-    } else if reader.consume("continue").is_ok() {
+        } else if initial.consume(";").is_ok() {
-      Ok(Piece::from(Statement::Continue,&start,&reader.marker()))
+            Ok(Piece::from(Statement::Semicolon, &start, &initial.marker()))
-    } else if reader.consume(";").is_ok() {
+        } else if let Ok(mut reader) = initial.clone().consume("local") {
-      Ok(Piece::from(Statement::Semicolon,&start,&reader.marker()))
-    } else if let Ok(mut reader) = reader.consume("local").cloned() {
-      reader.trim()?;
             if reader.consume("function").is_ok() {
-        reader.trim()?;
                 let name = reader.take::<Name>()?;
-        reader.trim()?;
                 let function = reader.take::<Function>()?;
-        restore(&mut reader);
+                *initial = *reader;
-        Ok(Piece::from(Statement::LocalFunction(name, function.it), &start, &function.null()))
+                Ok(Piece::from(
+                    Statement::LocalFunction(name, function.it),
+                    &start,
+                    &function.null(),
+                ))
             } else {
                 let names = reader.take::<Vec<Piece<Name>>>()?.it;
-        reader.trim()?;
                 reader.consume("=")?;
-        reader.trim()?;
                 let expressions = reader.take::<Vec<Piece<Expression>>>()?.it;
-        restore(&mut reader);
+                *initial = *reader;
-        Ok(Piece::from(Statement::Declaration(names,expressions),&start,&reader.marker()))
+                Ok(Piece::from(
+                    Statement::Declaration(names, expressions),
+                    &start,
+                    &reader.marker(),
+                ))
             }
-    } else if let Ok(mut reader) = reader.consume("function") {
+        } else if let Ok(mut reader) = initial.clone().consume("function") {
             let mut names = Vec::new();
             loop {
-        reader.trim()?;
                 if let Ok(name) = reader.take::<Name>() {
                     names.push(name);
-          reader.trim()?;
                     if !reader.consume(".").is_ok() {
-            break
+                        break;
                     }
                 }
             }
             let mut member = None;
             if reader.consume(":").is_ok() {
-        reader.trim()?;
                 member = Some(reader.take::<Name>()?);
             }
             let function = reader.take::<Function>()?;
-      restore(&mut reader);
+            *initial = *reader;
-      Ok(Piece::from(Statement::Function(names,member,function.it),&start,&reader.marker()))
+            Ok(Piece::from(
-    } else if let Ok(mut reader) = reader.consume("for") {
+                Statement::Function(names, member, function.it),
-      reader.trim()?;
+                &start,
-      let names = reader.take::<Vec<Piece<Name>>>()?.it; reader.trim()?;
+                &reader.marker(),
+            ))
+        } else if let Ok(mut reader) = initial.clone().consume("for") {
+            let names = reader.take::<Vec<Piece<Name>>>()?.it;
             let result = if names.len() > 1 {
                 let name = *names.first().unwrap().clone();
-        reader.consume("=")?; reader.trim()?;
+                reader.consume("=")?;
-        let begin = reader.take::<Expression>()?; reader.trim()?;
+                let begin = reader.take::<Expression>()?;
-        reader.consume(",")?; reader.trim()?;
+                reader.consume(",")?;
-        let finish = reader.take::<Expression>()?; reader.trim()?;
+                let finish = reader.take::<Expression>()?;
                 let delta = if reader.consume(",").is_ok() {
-          reader.trim()?;
                     Some(reader.take::<Expression>()?)
                 } else {
                     None
                 };
-        reader.consume("do")?; reader.trim()?;
+                reader.consume("do")?;
-        let block = reader.take::<Block>()?; reader.trim()?;
+                let block = reader.take::<Block>()?;
                 reader.consume("end")?;
-        Ok(Piece::from(Statement::Range(name,begin,finish,delta,block.it),&start,&reader.marker()))
+                Ok(Piece::from(
+                    Statement::Range(name, begin, finish, delta, block.it),
+                    &start,
+                    &reader.marker(),
+                ))
             } else {
-        reader.consume("in")?; reader.trim()?;
+                reader.consume("in")?;
-        let expressions = reader.take::<Vec<Piece<Expression>>>()?.it; reader.trim()?;
+                let expressions = reader.take::<Vec<Piece<Expression>>>()?.it;
-        reader.consume("do")?; reader.trim()?;
+                reader.consume("do")?;
-        let block = reader.take::<Block>()?; reader.trim()?;
+                let block = reader.take::<Block>()?;
                 reader.consume("end")?;
-        Ok(Piece::from(Statement::Iterator(names,expressions,block.it),&start,&reader.marker()))
+                Ok(Piece::from(
+                    Statement::Iterator(names, expressions, block.it),
+                    &start,
+                    &reader.marker(),
+                ))
             };
-      restore(&mut reader);
+            *initial = *reader;
             result
-    } else if let Ok(mut reader) = reader.consume("while") {
+        } else if let Ok(mut reader) = initial.clone().consume("while") {
-      reader.trim()?;
             let condition = reader.take::<Expression>()?;
-      reader.consume("do")?; reader.trim()?;
+            reader.consume("do")?;
-      let block = reader.take::<Block>()?; reader.trim()?;
+            let block = reader.take::<Block>()?;
             reader.consume("end")?;
-      restore(&mut reader);
+            *initial = *reader;
-      Ok(Piece::from(Statement::While(condition,block.it),&start,&reader.marker()))
+            Ok(Piece::from(
-    } else if let Ok(mut reader) = reader.consume("if") {
+                Statement::While(condition, block.it),
-      reader.trim()?;
+                &start,
+                &reader.marker(),
+            ))
+        } else if let Ok(mut reader) = initial.clone().consume("if") {
             let mut conditions = Vec::new();
             let mut blocks = Vec::new();
             let branch = || -> Result<(), Error> {
-        conditions.push(reader.take::<Expression>()?); reader.trim()?;
+                conditions.push(reader.take::<Expression>()?);
-        reader.consume("then")?; reader.trim()?;
+                reader.consume("then")?;
                 blocks.push(reader.take::<Block>()?.it);
                 Ok(())
             };
             branch()?;
             while reader.consume("elseif").is_ok() {
-        reader.trim()?;
                 branch()?;
             }
             let block = if reader.consume("else").is_ok() {
-        reader.trim()?;
                 Some(reader.take::<Block>()?.it)
             } else {
                 None
             };
             reader.consume("end")?;
-      restore(&mut reader);
+            *initial = *reader;
-      Ok(Piece::from(Statement::If(conditions,blocks,block),&start,&reader.marker()))
+            Ok(Piece::from(
-    } else if let Ok(mut reader) = reader.consume("goto") {
+                Statement::If(conditions, blocks, block),
-      reader.trim()?;
+                &start,
+                &reader.marker(),
+            ))
+        } else if let Ok(mut reader) = initial.clone().consume("goto") {
             let name = reader.take::<Name>()?;
-      restore(&mut reader);
+            *initial = *reader;
             Ok(Piece::from(Statement::Goto(name), &start, &reader.marker()))
-    } else if let Ok(mut reader) = reader.consume("do") {
+        } else if let Ok(mut reader) = initial.clone().consume("do") {
-      reader.trim()?;
             let block = reader.take::<Block>()?;
-      restore(&mut reader);
+            *initial = *reader;
-      Ok(Piece::from(Statement::Do(block.it),&start,&reader.marker()))
+            Ok(Piece::from(
-    } else if let Ok(mut reader) = reader.consume("repeat") {
+                Statement::Do(block.it),
-      reader.trim()?;
+                &start,
-      reader.consume("repeat")?; reader.trim()?;
+                &reader.marker(),
-      let block = reader.take::<Block>()?; reader.trim()?;
+            ))
-      reader.consume("until")?; reader.trim()?;
+        } else if let Ok(mut reader) = initial.clone().consume("repeat") {
+            reader.consume("repeat")?;
+            let block = reader.take::<Block>()?;
+            reader.consume("until")?;
             let condition = reader.take::<Expression>()?;
-      restore(&mut reader);
+            *initial = *reader;
-      Ok(Piece::from(Statement::Repeat(block.it,condition),&start,&reader.marker()))
+            Ok(Piece::from(
-    } else if let Ok(mut reader) = reader.consume("::") {
+                Statement::Repeat(block.it, condition),
+                &start,
+                &reader.marker(),
+            ))
+        } else if let Ok(mut reader) = initial.clone().consume("::") {
             let name = reader.take::<Name>()?;
             reader.consume("::")?;
-      restore(&mut reader);
+            *initial = *reader;
-      Ok(Piece::from(Statement::Label(name),&start,&reader.marker()))
+            Ok(Piece::from(
-    } else if let Ok(mut reader) =
+                Statement::Label(name),
+                &start,
+                &reader.marker(),
+            ))
+        } else {
+            reader.take::<Call>().map(|call| Statement::Call(call)).or_else(|| reader.take::)
+        }
+        
     }
 }
 
 impl Parse for Block {
     fn consume(reader: &mut Reader) -> Result<Piece<Block>, Error>
     where
-    Self: Sized
+        Self: Sized,
     {
         let mut statements = Vec::new();
+        let start = reader.marker();
         while let Ok(statement) = reader.take::<Statement>() {
             statements.push(statement);
         }
-    if statements.is_empty() {
+        let expressions = if reader.consume("return").is_ok() {
-      Ok(Piece::of(Block(statements),reader,0))
+            let result = reader.take::<Vec<Piece<Expression>>>()?;
+            reader.consume(";").ok();
+            result.it
         } else {
-      let first = statements.first().unwrap().null();
+            Vec::new()
-      let last = statements.last().unwrap().null();
+        };
-      Ok(Piece::from(Block(statements),&first,&last))
+        Ok(Piece::from(
-    }
+            Block(statements, expressions),
+            &start,
+            &reader.marker(),
+        ))
     }
 }