refactor(ast): Improve error type, remove unnecessary eof judge

src/lexer/err.rs

@@ -1,16 +1,7 @@
 use thiserror::Error;
 
-use crate::lexer::types::TokenValue;
+use crate::ast::err::ParseError;
 
-// #[derive(Debug, Clone, PartialEq, Eq, Error)]
-// pub enum ParseError {
-//     BlockStmt(#[from] BlockStmtError)
-// }
-// #[derive(Debug, Clone, PartialEq, Eq, Error)]
-// pub enum BlockStmtError {
-//     MissingLBrace,
-//     MissingRBrace,
-// }
 #[derive(Debug, Clone, PartialEq, Eq, Error)]
 pub enum LexingError {
     #[error("invalid int literal")]
@@ -23,15 +14,6 @@ pub enum LexingError {
     UnrecognizedToken(String),
 }
 #[derive(Debug, Clone, PartialEq, Eq, Error)]
-pub enum ParseError {
-    #[error("unexpected token {}, expect {}", .0, .1)]
-    UnexpectedToken(TokenValue, &'static str),
-    #[error("cannot combine with previous {}", .0)]
-    CantCombineWith(TokenValue),
-    #[error("expect {0} after")]
-    ExpectButEof(&'static str),
-}
-#[derive(Debug, Clone, PartialEq, Eq, Error)]
 pub enum FrontendError {
     #[error(transparent)]
     Lexing(#[from] LexingError),

src/lexer/types.rs

@@ -81,7 +81,7 @@ impl std::fmt::Display for TokenValue {
             TokenValue::Return => write!(f, "return"),
             TokenValue::Break => write!(f, "break"),
             TokenValue::Continue => write!(f, "continue"),
-            TokenValue::Eof => write!(f, "<EOF>"),
+            TokenValue::Eof => write!(f, "end of input"),
             TokenValue::Unrecognized => write!(f, "unrecognized"),
         }
     }