feat(lexer): Add diagnostic and impl error recovering

src/frontend/types.rs

@@ -1,4 +1,6 @@
-use strum::EnumString;
+use strum::{AsRefStr, EnumString};
+
+use crate::diagnostic::span::Span;
 
 
 #[derive(Debug, Clone, PartialEq, Eq)]
@@ -7,12 +9,6 @@ pub struct Token {
     pub span: Span,
 }
 
-#[derive(Debug, Clone, PartialEq, Eq)]
-pub struct Span {
-    pub line: usize,
-    pub column: usize,
-    pub length: usize,
-}
 
 #[derive(Debug, Clone, PartialEq, Eq)]
 pub enum TokenValue {
@@ -20,6 +16,61 @@ pub enum TokenValue {
     Ident(String),
     TypeIdent(TypeIdent),
     
+    Plus, Minus, Star, Slash, Percent,
+    Equal, DoubleEqual, Not, NotEqual, Less, LessEqual, Greater, GreaterEqual,
+
+    LParen, RParen,
+    LBrace, RBrace,
+    Comma, Semicolon,
+
+    If, Else, While, Return, Break, Continue,
+
+    // Eof,
+    Unrecognized,
+}
+impl std::fmt::Display for TokenValue {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        match self {
+            TokenValue::IntLit(i) => write!(f, "literal int: {}", i),
+            TokenValue::Ident(s) => write!(f, "identifier: {}", s),
+            TokenValue::TypeIdent(t) => write!(f, "type {}", t.as_ref()),
+            TokenValue::Plus => write!(f, "+"),
+            TokenValue::Minus => write!(f, "-"),
+            TokenValue::Star => write!(f, "*"),
+            TokenValue::Slash => write!(f, "/"),
+            TokenValue::Percent => write!(f, "%"),
+            TokenValue::Equal => write!(f, "="),
+            TokenValue::DoubleEqual => write!(f, "=="),
+            TokenValue::Not => write!(f, "!"),
+            TokenValue::NotEqual => write!(f, "!="),
+            TokenValue::Less => write!(f, "<"),
+            TokenValue::LessEqual => write!(f, "<="),
+            TokenValue::Greater => write!(f, ">"),
+            TokenValue::GreaterEqual => write!(f, ">="),
+            TokenValue::LParen => write!(f, "("),
+            TokenValue::RParen => write!(f, ")"),
+            TokenValue::LBrace => write!(f, "{{"),
+            TokenValue::RBrace => write!(f, "}}"),
+            TokenValue::Comma => write!(f, ","),
+            TokenValue::Semicolon => write!(f, ";"),
+            TokenValue::If => write!(f, "if"),
+            TokenValue::Else => write!(f, "else"),
+            TokenValue::While => write!(f, "while"),
+            TokenValue::Return => write!(f, "return"),
+            TokenValue::Break => write!(f, "break"),
+            TokenValue::Continue => write!(f, "continue"),
+            // TokenValue::Eof => write!(f, "<EOF>"),
+            TokenValue::Unrecognized => write!(f, "unrecognized"),
+        }
+    }
+}
+
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+pub enum TokenKind {
+    IntLit,
+    Ident,
+    TypeIdent,
+    
     Plus, Minus, Star, Slash, Percent,
     Equal, DoubleEqual, NotEqual, Less, LessEqual, Greater, GreaterEqual,
 
@@ -29,10 +80,10 @@ pub enum TokenValue {
 
     If, Else, While, Return, Break, Continue,
 
-    Eof,
-    Unrecognized(char),
+    // Eof,
+    Unrecognized,
 }
-#[derive(Debug, Clone, PartialEq, Eq, EnumString)]
+#[derive(Debug, Clone, PartialEq, Eq, EnumString, AsRefStr)]
 pub enum TypeIdent {
     #[strum(serialize = "int")]
     Int,