nodes + dyn stuff which is dumb and I'ma replace

src/v1/mod.rs

@@ -2,12 +2,27 @@ use std::io::{stdout, BufRead, BufReader};
 
 mod parser;
 
-use parser::{Module, Statement, TokenCursor};
+use parser::{Module, Node, NodeContainer, Statement, TokenCursor};
 
 pub fn parse_file(file: &str) {
-    match Module::parse(&mut TokenCursor::from(file)) {
+    let node = Node::<Module>::parse(&mut TokenCursor::from(file));
+    match node.inner {
         Err(err) => err.write_for(&mut stdout(), file).unwrap(),
-        Ok(module) => println!("{module:#?}"),
+        Ok(module) => {
+            println!("{module:#?}");
+            print_errors(module.children(), file)
+        },
+    };
+}
+
+pub fn print_errors(nodes: Vec<Node<Box<dyn NodeContainer>>>, file: &str) {
+    for node in &nodes {
+        if let Err(err) = &node.inner {
+            err.write_for(&mut stdout(), file).unwrap();
+        }
+    }
+    for node in nodes {
+        print_errors(node.children(), file)
     }
 }
 
@@ -16,7 +31,7 @@ pub fn run_stdin() {
         let str = &line.expect("failed to read line");
         let mut cursor = TokenCursor::from(&str[..]);
         let out = &mut stdout();
-        match Statement::parse(&mut cursor) {
+        match Node::<Statement>::parse(&mut cursor).inner {
             Ok(expr) => println!("{:?}", expr),
             Err(err) => err.write_for(out, str).unwrap(),
         }

src/v1/parser/body.rs

@@ -1,65 +1,81 @@
 use std::fmt::{Debug, Write};
 
-use super::token::{Keyword, Symbol, Token};
+use super::{
+    token::{Keyword, Symbol, Token}, Node, NodeContainer, Parsable
+};
 use crate::util::Padder;
 
 use super::{Expr, ParserError, TokenCursor};
 
+#[derive(Clone)]
 pub struct Body {
-    statements: Vec<Statement>,
+    statements: Vec<Node<Statement>>,
 }
 
+#[derive(Clone)]
 pub enum Statement {
-    Let(String, Expr),
-    Return(Expr),
-    Expr(Expr),
+    Let(String, Node<Expr>),
+    Return(Node<Expr>),
+    Expr(Node<Expr>),
 }
 
-impl Body {
-    pub fn parse(cursor: &mut TokenCursor) -> Result<Self, ParserError> {
+impl Parsable for Body {
+    fn parse(cursor: &mut TokenCursor) -> Result<Self, ParserError> {
         let mut statements = Vec::new();
+        let statement_end = &[Symbol::Semicolon, Symbol::CloseCurly];
         cursor.expect_sym(Symbol::OpenCurly)?;
+        if cursor.expect_peek()?.is_symbol(Symbol::CloseCurly) {
+            cursor.next();
+            return Ok(Self { statements });
+        }
         loop {
             let next = cursor.expect_peek()?;
             if next.is_symbol(Symbol::CloseCurly) {
                 cursor.next();
                 return Ok(Self { statements });
             }
-            statements.push(Statement::parse(cursor)?);
+            statements.push(Node::parse(cursor));
+            let next = cursor.expect_next()?;
+            match next.token {
+                Token::Symbol(Symbol::Semicolon) => continue,
+                Token::Symbol(Symbol::CloseCurly) => return Ok(Self { statements }),
+                _ => {
+                    let start = next.span.start;
+                    cursor
+                        .seek(|t| t.is_symbol_and(|s| statement_end.contains(&s)))
+                        .ok_or(ParserError::unexpected_end())?;
+                    let end = cursor.prev_end();
+                    let next = cursor.expect_next()?;
+                    let span = start.to(end);
+                    statements.push(Node::err(ParserError {
+                        msg: "Unexpected tokens".to_string(),
+                        spans: vec![span],
+                    }, span));
+                    if next.is_symbol(Symbol::CloseCurly) {
+                        return Ok(Self { statements });
+                    }
+                }
+            }
         }
     }
 }
 
-impl Statement {
-    pub fn parse(cursor: &mut TokenCursor) -> Result<Self, ParserError> {
+impl Parsable for Statement {
+    fn parse(cursor: &mut TokenCursor) -> Result<Self, ParserError> {
         let next = cursor.expect_peek()?;
         Ok(match next.token {
             Token::Keyword(Keyword::Let) => {
                 cursor.next();
                 let name = cursor.expect_ident()?;
                 cursor.expect_sym(Symbol::Equals)?;
-                let expr = Expr::parse(cursor)?;
-                cursor.expect_sym(Symbol::Semicolon)?;
+                let expr = Node::parse(cursor);
                 Self::Let(name, expr)
             }
             Token::Keyword(Keyword::Return) => {
                 cursor.next();
-                let expr = Expr::parse(cursor)?;
-                cursor.expect_sym(Symbol::Semicolon)?;
-                Self::Return(expr)
-            }
-            _ => {
-                let expr = Expr::parse(cursor)?;
-                let next = cursor.expect_peek()?;
-                if next.is_symbol(Symbol::Semicolon) {
-                    cursor.next();
-                    Self::Expr(expr)
-                } else if next.is_symbol(Symbol::CloseCurly) {
-                    Self::Return(expr)
-                } else {
-                    return Err(ParserError::unexpected_token(next, "a ';' or '}'"));
-                }
+                Self::Return(Node::parse(cursor))
             }
+            _ => Self::Expr(Node::parse(cursor)),
         })
     }
 }
@@ -104,3 +120,19 @@ impl Debug for Body {
         Ok(())
     }
 }
+
+impl NodeContainer for Body {
+    fn children(&self) -> Vec<Node<Box<dyn NodeContainer>>> {
+        self.statements.iter().map(|f| f.containerr()).collect()
+    }
+}
+
+impl NodeContainer for Statement {
+    fn children(&self) -> Vec<Node<Box<dyn NodeContainer>>> {
+        match self {
+            Statement::Let(_, e) => vec![e.containerr()],
+            Statement::Return(e) => vec![e.containerr()],
+            Statement::Expr(e) => vec![e.containerr()],
+        }
+    }
+}

src/v1/parser/cursor.rs

@@ -1,19 +1,23 @@
-use std::ops::{Deref, DerefMut};
-
 use super::error::ParserError;
 use super::token::{CharCursor, Keyword, Symbol, Token, TokenInstance};
+use super::FilePos;
 
 pub struct TokenCursor<'a> {
     cursor: CharCursor<'a>,
     next: Option<TokenInstance>,
+    next_pos: FilePos,
+    prev_end: FilePos,
 }
 
 impl<'a> TokenCursor<'a> {
     pub fn next(&mut self) -> Option<TokenInstance> {
+        self.prev_end = self.cursor.prev_pos();
+        self.next_pos = self.cursor.next_pos();
         std::mem::replace(&mut self.next, TokenInstance::parse(&mut self.cursor))
     }
     pub fn expect_next(&mut self) -> Result<TokenInstance, ParserError> {
-        self.next().ok_or(ParserError::unexpected_end())
+        self.peek().ok_or(ParserError::unexpected_end())?;
+        Ok(self.next().unwrap())
     }
     pub fn expect_token(&mut self, t: Token) -> Result<(), ParserError> {
         let next = self.expect_next()?;
@@ -26,6 +30,20 @@ impl<'a> TokenCursor<'a> {
     pub fn expect_sym(&mut self, symbol: Symbol) -> Result<(), ParserError> {
         self.expect_token(Token::Symbol(symbol))
     }
+    pub fn seek_sym(&mut self, symbol: Symbol) {
+        while self
+            .next()
+            .is_some_and(|n| n.token != Token::Symbol(symbol))
+        {}
+    }
+    pub fn seek(&mut self, f: impl Fn(&TokenInstance) -> bool) -> Option<&TokenInstance> {
+        loop {
+            if f(self.peek()?) {
+                return self.peek();
+            }
+            self.next();
+        }
+    }
     pub fn expect_kw(&mut self, kw: Keyword) -> Result<(), ParserError> {
         self.expect_token(Token::Keyword(kw))
     }
@@ -45,6 +63,12 @@ impl<'a> TokenCursor<'a> {
     pub fn chars(&mut self) -> &mut CharCursor<'a> {
         &mut self.cursor
     }
+    pub fn prev_end(&self) -> FilePos {
+        self.prev_end
+    }
+    pub fn next_pos(&self) -> FilePos {
+        self.next_pos
+    }
 }
 
 impl<'a> From<&'a str> for TokenCursor<'a> {
@@ -56,6 +80,11 @@ impl<'a> From<&'a str> for TokenCursor<'a> {
 impl<'a> From<CharCursor<'a>> for TokenCursor<'a> {
     fn from(mut cursor: CharCursor<'a>) -> Self {
         let cur = TokenInstance::parse(&mut cursor);
-        Self { cursor, next: cur }
+        Self {
+            cursor,
+            next: cur,
+            next_pos: FilePos::start(),
+            prev_end: FilePos::start(),
+        }
     }
 }

src/v1/parser/error.rs

@@ -1,31 +1,35 @@
-use super::{token::{FileRegion, TokenInstance}, FilePos};
+use super::{
+    token::{FileSpan, TokenInstance},
+    FilePos,
+};
 
-#[derive(Debug)]
+#[derive(Debug, Clone)]
 pub struct ParserError {
     pub msg: String,
-    pub regions: Vec<FileRegion>,
+    pub spans: Vec<FileSpan>,
+}
+
+pub struct ParserErrors {
+    pub errs: Vec<ParserError>,
 }
 
 impl ParserError {
     pub fn from_instances(instances: &[&TokenInstance], msg: String) -> Self {
         ParserError {
             msg,
-            regions: instances.iter().map(|i| i.region).collect(),
+            spans: instances.iter().map(|i| i.span).collect(),
         }
     }
     pub fn from_msg(msg: String) -> Self {
         Self {
             msg,
-            regions: Vec::new(),
+            spans: Vec::new(),
         }
     }
     pub fn at(pos: FilePos, msg: String) -> Self {
         Self {
             msg,
-            regions: vec![FileRegion {
-                start: pos,
-                end: pos,
-            }],
+            spans: vec![FileSpan::at(pos)],
         }
     }
     pub fn unexpected_end() -> Self {
@@ -39,12 +43,17 @@ impl ParserError {
         )
     }
     pub fn write_for(&self, writer: &mut impl std::io::Write, file: &str) -> std::io::Result<()> {
-        let after = if self.regions.is_empty() { "" } else { ":" };
+        let after = if self.spans.is_empty() { "" } else { ":" };
         writeln!(writer, "error: {}{}", self.msg, after)?;
-        for reg in &self.regions {
-            reg.write_for(writer, file)?;
+        for span in &self.spans {
+            span.write_for(writer, file)?;
         }
         Ok(())
     }
 }
 
+impl ParserErrors {
+    pub fn add(&mut self, err: ParserError) {
+        self.errs.push(err);
+    }
+}

src/v1/parser/expr.rs

@@ -1,14 +1,15 @@
 use std::fmt::{Debug, Write};
 
 use super::token::{Symbol, Token};
-use super::{Body, Number, ParserError, TokenCursor, Val};
+use super::{Body, Node, NodeContainer, Parsable, ParserError, TokenCursor, Val};
 
+#[derive(Clone)]
 pub enum Expr {
-    Val(Val),
+    Val(Node<Val>),
     Ident(String),
-    BinaryOp(Operator, Box<Expr>, Box<Expr>),
-    Block(Body),
-    Call(Box<Expr>, Vec<Expr>),
+    BinaryOp(Operator, Node<Box<Expr>>, Node<Box<Expr>>),
+    Block(Node<Body>),
+    Call(Node<Box<Expr>>, Vec<Node<Expr>>),
 }
 
 #[derive(Debug, PartialEq, Eq, Clone, Copy)]
@@ -22,64 +23,78 @@ pub enum Operator {
     Access,
 }
 
-impl Expr {
-    pub fn parse(cursor: &mut TokenCursor) -> Result<Self, ParserError> {
+impl Parsable for Expr {
+    fn parse(cursor: &mut TokenCursor) -> Result<Self, ParserError> {
+        let start = cursor.next_pos();
         let Some(next) = cursor.peek() else {
-            return Ok(Expr::Val(Val::Unit));
+            return Ok(Expr::Val(Node::new(
+                Val::Unit,
+                cursor.next_pos().char_span(),
+            )));
         };
         let mut e1 = if next.is_symbol(Symbol::OpenParen) {
             cursor.next();
-            let expr = Self::parse(cursor)?;
-            cursor.expect_sym(Symbol::CloseParen)?;
-            expr
+            let expr = Node::parse(cursor);
+            if expr.is_ok() {
+                cursor.expect_sym(Symbol::CloseParen)?;
+            } else {
+                cursor.seek_sym(Symbol::CloseParen);
+            }
+            expr.take()?
         } else if next.is_symbol(Symbol::OpenCurly) {
-            let expr = Body::parse(cursor)?;
-            Expr::Block(expr)
+            Self::Block(Node::parse(cursor))
+        } else if let Some(val) = Node::maybe_parse(cursor) {
+            Self::Val(val)
         } else {
-            Self::parse_unit(cursor)?
+            let next = cursor.peek().unwrap();
+            match &next.token {
+                Token::Ident(name) => {
+                    let name = name.to_string();
+                    cursor.next();
+                    Self::Ident(name)
+                }
+                _ => {
+                    return Ok(Expr::Val(Node::new(
+                        Val::Unit,
+                        cursor.next_pos().char_span(),
+                    )))
+                }
+            }
         };
         let Some(mut next) = cursor.peek() else {
             return Ok(e1);
         };
         while next.is_symbol(Symbol::OpenParen) {
             cursor.next();
-            let inner = Self::parse(cursor)?;
+            let inner = Node::parse(cursor);
             cursor.expect_sym(Symbol::CloseParen)?;
-            e1 = Self::Call(Box::new(e1), vec![inner]);
+            let end = cursor.prev_end();
+            e1 = Self::Call(Node::new(Box::new(e1), start.to(end)), vec![inner]);
             let Some(next2) = cursor.peek() else {
                 return Ok(e1);
             };
             next = next2
         }
-        Ok(if let Some(op) = Operator::from_token(&next.token) {
+        let end = cursor.prev_end();
+        Ok(if let Some(mut op) = Operator::from_token(&next.token) {
             cursor.next();
-            let e2 = Self::parse(cursor)?;
-            if let Self::BinaryOp(op_next, e3, e4) = e2 {
-                if op.presedence() > op_next.presedence() {
-                    Self::BinaryOp(op_next, Box::new(Self::BinaryOp(op, Box::new(e1), e3)), e4)
-                } else {
-                    Self::BinaryOp(op, Box::new(e1), Box::new(Self::BinaryOp(op_next, e3, e4)))
+            let mut n1 = Node::new(Box::new(e1), start.to(end));
+            let mut n2 = Node::<Self>::parse(cursor);
+            if let Ok(Self::BinaryOp(op2, n21, n22)) = &*n2 {
+                if op.presedence() > op2.presedence() {
+                    n1 = Node::new(
+                        Box::new(Self::BinaryOp(op, n1, n21.clone())),
+                        start.to(n21.span.end),
+                    );
+                    op = *op2;
+                    n2 = n22.clone().unbx();
                 }
-            } else {
-                Self::BinaryOp(op, Box::new(e1), Box::new(e2))
             }
+            Self::BinaryOp(op, n1, n2.bx())
         } else {
             e1
         })
     }
-    fn parse_unit(cursor: &mut TokenCursor) -> Result<Self, ParserError> {
-        if let Some(val) = Val::parse(cursor)? {
-            return Ok(Self::Val(val));
-        }
-        let inst = cursor.expect_next()?;
-        match &inst.token {
-            Token::Ident(name) => Ok(Self::Ident(name.to_string())),
-            _ => Err(ParserError::unexpected_token(
-                &inst,
-                "an identifier or value",
-            )),
-        }
-    }
 }
 
 impl Operator {
@@ -166,3 +181,18 @@ impl Debug for Expr {
         Ok(())
     }
 }
+
+impl NodeContainer for Expr {
+    fn children(&self) -> Vec<Node<Box<dyn NodeContainer>>> {
+        match self {
+            Expr::Val(_) => Vec::new(),
+            Expr::Ident(_) => Vec::new(),
+            Expr::BinaryOp(_, e1, e2) => vec![e1.container(), e2.container()],
+            Expr::Block(b) => vec![b.containerr()],
+            Expr::Call(e1, rest) => [e1.container()]
+                .into_iter()
+                .chain(rest.iter().map(|e| e.containerr()))
+                .collect(),
+        }
+    }
+}

src/v1/parser/mod.rs

@@ -6,34 +6,37 @@ mod error;
 mod expr;
 mod token;
 mod val;
+mod node;
 
 pub use body::*;
 pub use cursor::*;
 pub use error::*;
 pub use expr::*;
 pub use val::*;
+pub use node::*;
 
 use token::*;
 
 #[derive(Debug)]
 pub struct Module {
-    functions: Vec<Function>,
+    functions: Vec<Node<Function>>,
 }
 
+#[derive(Clone)]
 pub struct Function {
     pub name: String,
-    pub body: Body,
+    pub body: Node<Body>,
 }
 
-impl Module {
-    pub fn parse(cursor: &mut TokenCursor) -> Result<Self, ParserError> {
+impl Parsable for Module {
+    fn parse(cursor: &mut TokenCursor) -> Result<Self, ParserError> {
         let mut functions = Vec::new();
         loop {
             let Some(next) = cursor.peek() else {
                 return Ok(Self { functions });
             };
             if next.is_keyword(Keyword::Fn) {
-                functions.push(Function::parse(cursor)?);
+                functions.push(Node::parse(cursor));
             } else {
                 return Err(ParserError::unexpected_token(next, "fn"));
             }
@@ -41,13 +44,13 @@ impl Module {
     }
 }
 
-impl Function {
-    pub fn parse(cursor: &mut TokenCursor) -> Result<Self, ParserError> {
+impl Parsable for Function {
+    fn parse(cursor: &mut TokenCursor) -> Result<Self, ParserError> {
         cursor.expect_kw(Keyword::Fn)?;
         let name = cursor.expect_ident()?;
         cursor.expect_sym(Symbol::OpenParen)?;
         cursor.expect_sym(Symbol::CloseParen)?;
-        let body = Body::parse(cursor)?;
+        let body = Node::parse(cursor);
         Ok(Self { name, body })
     }
 }
@@ -61,3 +64,15 @@ impl Debug for Function {
         Ok(())
     }
 }
+
+impl NodeContainer for Module {
+    fn children(&self) -> Vec<Node<Box<dyn NodeContainer>>> {
+        self.functions.iter().map(|f| f.containerr()).collect()
+    }
+}
+
+impl NodeContainer for Function {
+    fn children(&self) -> Vec<Node<Box<dyn NodeContainer>>> {
+        vec![self.body.containerr()]
+    }
+}

src/v1/parser/node.rs

@@ -0,0 +1,132 @@
+use std::{
+    fmt::Debug,
+    ops::{Deref, DerefMut},
+};
+
+use super::{FileSpan, ParserError, TokenCursor};
+
+#[derive(Clone)]
+pub struct Node<T> {
+    pub inner: Result<T, ParserError>,
+    pub span: FileSpan,
+}
+
+pub trait Parsable: Sized {
+    fn parse(cursor: &mut TokenCursor) -> Result<Self, ParserError>;
+}
+
+pub trait MaybeParsable: Sized {
+    fn maybe_parse(cursor: &mut TokenCursor) -> Result<Option<Self>, ParserError>;
+}
+
+pub trait NodeContainer {
+    fn children(&self) -> Vec<Node<Box<dyn NodeContainer>>>;
+}
+
+impl<T: NodeContainer + ?Sized> NodeContainer for Node<Box<T>> {
+    fn children(&self) -> Vec<Node<Box<dyn NodeContainer>>> {
+        match &self.inner {
+            Ok(v) => v.children(),
+            Err(_) => Vec::new(),
+        }
+    }
+}
+
+impl<T: Parsable> Node<T> {
+    pub fn parse(cursor: &mut TokenCursor) -> Self {
+        let start = cursor.next_pos();
+        let inner = T::parse(cursor);
+        let end = cursor.prev_end();
+        Self {
+            inner,
+            span: start.to(end),
+        }
+    }
+}
+
+impl<T: MaybeParsable> Node<T> {
+    pub fn maybe_parse(cursor: &mut TokenCursor) -> Option<Self> {
+        let start = cursor.next_pos();
+        let inner = match T::maybe_parse(cursor) {
+            Ok(v) => Ok(v?),
+            Err(e) => Err(e),
+        };
+        let end = cursor.prev_end();
+        Some(Self {
+            inner,
+            span: start.to(end),
+        })
+    }
+}
+
+impl<T> Node<T> {
+    pub fn new(inner: T, span: FileSpan) -> Self {
+        Self {
+            inner: Ok(inner),
+            span,
+        }
+    }
+    pub fn err(inner: ParserError, span: FileSpan) -> Self {
+        Self {
+            inner: Err(inner),
+            span,
+        }
+    }
+    pub fn take(self) -> Result<T, ParserError> {
+        self.inner
+    }
+    pub fn bx(self) -> Node<Box<T>> {
+        Node {
+            inner: self.inner.map(|v| Box::new(v)),
+            span: self.span,
+        }
+    }
+}
+
+impl<T: NodeContainer + Clone + 'static> Node<T> {
+    pub fn containerr(&self) -> Node<Box<dyn NodeContainer>> {
+        Node {
+            inner: self.clone().inner.map(|v| Box::new(v) as Box<dyn NodeContainer>),
+            span: self.span,
+        }
+    }
+}
+
+impl<T> Node<Box<T>> {
+    pub fn unbx(self) -> Node<T> {
+        Node {
+            inner: self.inner.map(|v| *v),
+            span: self.span,
+        }
+    }
+}
+impl<T: NodeContainer + Clone + 'static> Node<Box<T>> {
+    pub fn container(&self) -> Node<Box<dyn NodeContainer>> {
+        Node {
+            inner: self.clone().inner.map(|v| v as Box<dyn NodeContainer>),
+            span: self.span,
+        }
+    }
+}
+
+impl<T> Deref for Node<T> {
+    type Target = Result<T, ParserError>;
+    fn deref(&self) -> &Self::Target {
+        &self.inner
+    }
+}
+
+impl<T> DerefMut for Node<T> {
+    fn deref_mut(&mut self) -> &mut Self::Target {
+        &mut self.inner
+    }
+}
+
+impl<T: Debug> Debug for Node<T> {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        match &self.inner {
+            Ok(v) => v.fmt(f),
+            Err(_) => f.write_str("{error}"),
+        }
+    }
+}

src/v1/parser/token/cursor.rs

@@ -1,12 +1,11 @@
 use std::{iter::Peekable, str::Chars};
 
-use crate::v1::parser::ParserError;
-
+use super::super::ParserError;
 use super::FilePos;
 
 pub struct CharCursor<'a> {
     chars: Peekable<Chars<'a>>,
-    pos: FilePos,
+    next_pos: FilePos,
     prev_pos: FilePos,
 }
 
@@ -39,12 +38,12 @@ impl CharCursor<'_> {
         let Some(next) = self.chars.next() else {
             return;
         };
-        self.prev_pos = self.pos;
+        self.prev_pos = self.next_pos;
         if next == '\n' {
-            self.pos.col = 0;
-            self.pos.line += 1;
+            self.next_pos.col = 0;
+            self.next_pos.line += 1;
         } else {
-            self.pos.col += 1;
+            self.next_pos.col += 1;
         }
     }
     pub fn advance_if(&mut self, c: char) -> bool {
@@ -57,11 +56,10 @@ impl CharCursor<'_> {
         false
     }
     pub fn expect_next(&mut self) -> Result<char, ParserError> {
-        self.next()
-            .ok_or(ParserError::from_msg("Unexpected end of input".to_string()))
+        self.next().ok_or(ParserError::unexpected_end())
     }
-    pub fn pos(&self) -> FilePos {
-        self.pos
+    pub fn next_pos(&self) -> FilePos {
+        self.next_pos
     }
     pub fn prev_pos(&self) -> FilePos {
         self.prev_pos
@@ -72,7 +70,7 @@ impl<'a> From<&'a str> for CharCursor<'a> {
     fn from(value: &'a str) -> Self {
         Self {
             chars: value.chars().peekable(),
-            pos: FilePos::start(),
+            next_pos: FilePos::start(),
             prev_pos: FilePos::start(),
         }
     }

src/v1/parser/token/file.rs

@@ -5,7 +5,7 @@ pub struct FilePos {
 }
 
 #[derive(Debug, Clone, Copy)]
-pub struct FileRegion {
+pub struct FileSpan {
     pub start: FilePos,
     pub end: FilePos,
 }
@@ -16,10 +16,25 @@ impl FilePos {
     }
 }
 
+impl FilePos {
+    pub fn to(self, end: FilePos) -> FileSpan {
+        FileSpan { start: self, end }
+    }
+    pub fn char_span(self) -> FileSpan {
+        FileSpan::at(self)
+    }
+}
+
 const BEFORE: usize = 1;
 const AFTER: usize = 1;
 
-impl FileRegion {
+impl FileSpan {
+    pub fn at(pos: FilePos) -> Self {
+        Self {
+            start: pos,
+            end: pos,
+        }
+    }
     pub fn write_for(&self, writer: &mut impl std::io::Write, file: &str) -> std::io::Result<()> {
         let start = self.start.line.saturating_sub(BEFORE);
         let num_before = self.start.line - start;

src/v1/parser/token/mod.rs

@@ -3,6 +3,8 @@ mod file;
 mod keyword;
 mod symbol;
 
+use std::ops::Deref;
+
 pub use cursor::*;
 pub use file::*;
 pub use keyword::*;
@@ -15,17 +17,17 @@ pub enum Token {
     Keyword(Keyword),
 }
 
-#[derive(Debug)]
+#[derive(Clone)]
 pub struct TokenInstance {
     pub token: Token,
-    pub region: FileRegion,
+    pub span: FileSpan,
 }
 
 impl TokenInstance {
     pub fn parse(cursor: &mut CharCursor) -> Option<TokenInstance> {
         cursor.skip_whitespace();
         cursor.peek()?;
-        let start = cursor.pos();
+        let start = cursor.next_pos();
         if let Some(s) = Symbol::parse(cursor) {
             if s == Symbol::DoubleSlash {
                 while cursor.next() != Some('\n') {}
@@ -34,7 +36,7 @@ impl TokenInstance {
             let end = cursor.prev_pos();
             return Some(Self {
                 token: Token::Symbol(s),
-                region: FileRegion { start, end },
+                span: FileSpan { start, end },
             });
         }
         let mut word = String::new();
@@ -53,7 +55,7 @@ impl TokenInstance {
         };
         Some(Self {
             token,
-            region: FileRegion { start, end },
+            span: FileSpan { start, end },
         })
     }
 }
@@ -65,6 +67,12 @@ impl Token {
             _ => false,
         }
     }
+    pub fn is_symbol_and(&self, f: impl Fn(Symbol) -> bool) -> bool {
+        match self {
+            Token::Symbol(s) => f(*s),
+            _ => false,
+        }
+    }
     pub fn is_keyword(&self, kw: Keyword) -> bool {
         match self {
             Token::Keyword(k) => *k == kw,
@@ -73,11 +81,10 @@ impl Token {
     }
 }
 
-impl TokenInstance {
-    pub fn is_keyword(&self, kw: Keyword) -> bool {
-        self.token.is_keyword(kw)
-    }
-    pub fn is_symbol(&self, symbol: Symbol) -> bool {
-        self.token.is_symbol(symbol)
+impl Deref for TokenInstance {
+    type Target = Token;
+
+    fn deref(&self) -> &Self::Target {
+        &self.token
     }
 }

src/v1/parser/val.rs

@@ -1,7 +1,7 @@
-use super::{CharCursor, ParserError, Symbol, Token, TokenCursor};
+use super::{CharCursor, MaybeParsable, NodeContainer, ParserError, Symbol, Token, TokenCursor};
 use std::fmt::Debug;
 
-#[derive(PartialEq, Eq)]
+#[derive(Clone, PartialEq, Eq)]
 pub enum Val {
     String(String),
     Char(char),
@@ -9,15 +9,15 @@ pub enum Val {
     Unit,
 }
 
-#[derive(PartialEq, Eq)]
+#[derive(Clone, PartialEq, Eq)]
 pub struct Number {
     pub whole: String,
     pub decimal: Option<String>,
     pub ty: Option<String>,
 }
 
-impl Val {
-    pub fn parse(cursor: &mut TokenCursor) -> Result<Option<Self>, ParserError> {
+impl MaybeParsable for Val {
+    fn maybe_parse(cursor: &mut TokenCursor) -> Result<Option<Self>, ParserError> {
         let inst = cursor.expect_peek()?;
         let mut res = match &inst.token {
             Token::Symbol(Symbol::SingleQuote) => {
@@ -108,3 +108,4 @@ impl Debug for Number {
         Ok(())
     }
 }
+

src/v2/parser/body.rs

@@ -109,7 +109,7 @@ impl Debug for Body {
             let mut padder = Padder::new(f);
             for s in &self.statements {
                 // they don't expose wrap_buf :grief:
-                write!(padder, "{s:?}\n")?;
+                writeln!(padder, "{s:?}")?;
             }
             write!(f, "}}")?;
         } else {

test.lang

@@ -3,7 +3,7 @@ fn main() {
     let y = 4 + 4 + 5;
     let z = 1 * 2 - 3 / test * 4;
     let r = 1-2.5 + 3;
-    let w = 1 * (2 - 3) / "test" - 7;
+    let w = 1 * (2 - 3) / "test" - 7
     let a = test('3');
     let c = '3' ;
     test(5);