mu

rust/src/compiler.rs

@@ -1,4 +1,4 @@
-use crate::scanner::{Scanner, TokenKind};
+use crate::scanner::Scanner;
 use color_eyre::eyre::Result;
 
 pub fn compile(source: &str) -> Result<()> {

rust/src/scanner.rs

@@ -4,6 +4,10 @@ pub struct Scanner<'a> {
     line: usize,
 }
 
+fn is_alpha(c: char) -> bool {
+    c.is_ascii_alphabetic() || c == '_'
+}
+
 impl<'a> Scanner<'a> {
     pub fn new(source: &'a str) -> Self {
         Self {
@@ -13,22 +17,6 @@ impl<'a> Scanner<'a> {
         }
     }
 
-    fn make_token(&self, kind: TokenKind) -> Token<'a> {
-        Token {
-            kind,
-            value: std::str::from_utf8(&self.source[..self.current]).unwrap(),
-            line: self.line,
-        }
-    }
-
-    fn error_token(&self, message: &'static str) -> Token<'a> {
-        Token {
-            kind: TokenKind::Error,
-            value: message,
-            line: self.line,
-        }
-    }
-
     fn advance(&mut self) -> char {
         self.current += 1;
         self.source[self.current - 1] as char
@@ -75,7 +63,7 @@ impl<'a> Scanner<'a> {
         self.source.get(self.current).map(|&x| x as char)
     }
 
-    fn peek_next(&mut self) -> Option<char> {
+    fn peek_next(&self) -> Option<char> {
         self.source.get(self.current + 1).map(|&x| x as char)
     }
 
@@ -89,10 +77,11 @@ impl<'a> Scanner<'a> {
 
         if self.peek().is_none() {
             // Maybe this should return an Err?
-            return self.error_token("Unterminated string.");
+            return Token::error(&self, "Unterminated string.");
         }
 
         self.advance();
+        // Token::new(&self, TokenKind::String)
         self.make_token(TokenKind::String)
     }
 
@@ -109,6 +98,7 @@ impl<'a> Scanner<'a> {
             }
         }
 
+        // Token::new(&self, TokenKind::Number)
         self.make_token(TokenKind::Number)
     }
 
@@ -117,6 +107,7 @@ impl<'a> Scanner<'a> {
             self.advance();
         }
 
+        // Token::new(&self, self.identifier_type())
         self.make_token(self.identifier_type())
     }
 
@@ -147,6 +138,14 @@ impl<'a> Scanner<'a> {
             _ => TokenKind::Identifier,
         }
     }
+
+    fn make_token(&self, kind: TokenKind) -> Token<'a> {
+        Token {
+            kind: TokenKind::And,
+            value: std::str::from_utf8(&self.source[..self.current]).unwrap(),
+            line: self.line,
+        }
+    }
 }
 
 impl<'a> Iterator for Scanner<'a> {
@@ -159,61 +158,76 @@ impl<'a> Iterator for Scanner<'a> {
         Some(match self.advance() {
             c if is_alpha(c) => self.identifier(),
             c if c.is_ascii_digit() => self.number(),
-            '(' => self.make_token(TokenKind::LeftParen),
-            ')' => self.make_token(TokenKind::RightParen),
-            '{' => self.make_token(TokenKind::LeftBrace),
-            '}' => self.make_token(TokenKind::RightBrace),
-            ';' => self.make_token(TokenKind::Semicolon),
-            ',' => self.make_token(TokenKind::Comma),
-            '.' => self.make_token(TokenKind::Dot),
-            '-' => self.make_token(TokenKind::Minus),
-            '+' => self.make_token(TokenKind::Plus),
-            '/' => self.make_token(TokenKind::Slash),
-            '*' => self.make_token(TokenKind::Star),
-            '!' => {
-                if self.is_match('=') {
-                    self.make_token(TokenKind::BangEqual)
-                } else {
-                    self.make_token(TokenKind::Bang)
-                }
-            }
-            '=' => {
-                if self.is_match('=') {
-                    self.make_token(TokenKind::EqualEqual)
-                } else {
-                    self.make_token(TokenKind::Equal)
-                }
-            }
-            '<' => {
-                if self.is_match('=') {
-                    self.make_token(TokenKind::LessEqual)
-                } else {
-                    self.make_token(TokenKind::Less)
-                }
-            }
-            '>' => {
-                if self.is_match('=') {
-                    self.make_token(TokenKind::GreaterEqual)
-                } else {
-                    self.make_token(TokenKind::Greater)
-                }
-            }
-            '"' => self.string(),
-            _ => self.error_token("Unexpected character."),
+            '(' => Token::new(self, TokenKind::LeftParen),
+            // '(' => self.make_token(TokenKind::LeftParen),
+        //     ')' => self.make_token(TokenKind::RightParen),
+        //     '{' => self.make_token(TokenKind::LeftBrace),
+        //     '}' => self.make_token(TokenKind::RightBrace),
+        //     ';' => self.make_token(TokenKind::Semicolon),
+        //     ',' => self.make_token(TokenKind::Comma),
+        //     '.' => self.make_token(TokenKind::Dot),
+        //     '-' => self.make_token(TokenKind::Minus),
+        //     '+' => self.make_token(TokenKind::Plus),
+        //     '/' => self.make_token(TokenKind::Slash),
+        //     '*' => self.make_token(TokenKind::Star),
+        //     '!' => {
+        //         if self.is_match('=') {
+        //             self.make_token(TokenKind::BangEqual)
+        //         } else {
+        //             self.make_token(TokenKind::Bang)
+        //         }
+        //     }
+        //     '=' => {
+        //         if self.is_match('=') {
+        //             self.make_token(TokenKind::EqualEqual)
+        //         } else {
+        //             self.make_token(TokenKind::Equal)
+        //         }
+        //     }
+        //     '<' => {
+        //         if self.is_match('=') {
+        //             self.make_token(TokenKind::LessEqual)
+        //         } else {
+        //             self.make_token(TokenKind::Less)
+        //         }
+        //     }
+        //     '>' => {
+        //         if self.is_match('=') {
+        //             self.make_token(TokenKind::GreaterEqual)
+        //         } else {
+        //             self.make_token(TokenKind::Greater)
+        //         }
+        //     }
+        //     '"' => self.string(),
+            _ => Token::error(self, "Unexpected character."),
         })
     }
 }
 
-fn is_alpha(c: char) -> bool {
-    c.is_ascii_alphabetic() || c == '_'
-}
-
 pub struct Token<'a> {
     pub kind: TokenKind,
     pub value: &'a str,
     pub line: usize,
 }
 
+impl<'a> Token<'a> {
+    fn new(scanner: &Scanner<'a>, kind: TokenKind) -> Self {
+        Token {
+            kind,
+            value: std::str::from_utf8(&scanner.source[..scanner.current]).unwrap(),
+            line: scanner.line,
+        }
+    }
+
+    fn error(scanner: &Scanner, message: &'static str) -> Self {
+        Token {
+            kind: TokenKind::Error,
+            value: message,
+            line: scanner.line,
+        }
+    }
+}
+
 #[derive(Debug, PartialEq)]
 pub enum TokenKind {
     // Single-character tokens.