diff options
Diffstat (limited to 'users/tazjin/rlox/src')
-rw-r--r-- | users/tazjin/rlox/src/scanner.rs | 47 |
1 files changed, 41 insertions, 6 deletions
diff --git a/users/tazjin/rlox/src/scanner.rs b/users/tazjin/rlox/src/scanner.rs index c6db9de8c5d0..e0b04981b4a4 100644 --- a/users/tazjin/rlox/src/scanner.rs +++ b/users/tazjin/rlox/src/scanner.rs @@ -26,7 +26,7 @@ pub enum TokenKind { LessEqual, // Literals. - Identifier, + Identifier(String), String(String), Number(f64), @@ -120,15 +120,18 @@ impl<'a> Scanner<'a> { } // ignore whitespace - ' ' => {} - '\r' => {} - '\t' => {} - '\n' => self.line += 1, + ws if ws.is_whitespace() => { + if ws == '\n' { + self.line += 1 + } + } '"' => self.scan_string(), digit if digit.is_digit(10) => self.scan_number(), + chr if chr.is_alphabetic() || chr == '_' => self.scan_identifier(), + unexpected => self.errors.push(Error { line: self.line, kind: ErrorKind::UnexpectedChar(unexpected), @@ -162,7 +165,7 @@ impl<'a> Scanner<'a> { } fn peek_next(&self) -> char { - if (self.current + 1 >= self.source.len()) { + if self.current + 1 >= self.source.len() { return '\0'; } else { return self.source[self.current + 1]; @@ -220,12 +223,44 @@ impl<'a> Scanner<'a> { self.add_token(TokenKind::Number(num)); } + fn scan_identifier(&mut self) { + while self.peek().is_alphanumeric() || self.peek() == '_' { + self.advance(); + } + + let ident: String = self.source[self.start..self.current].iter().collect(); + + // Determine whether this is an identifier, or a keyword: + let token_kind = match ident.as_str() { + "and" => TokenKind::And, + "class" => TokenKind::Class, + "else" => TokenKind::Else, + "false" => TokenKind::False, + "for" => TokenKind::For, + "fun" => TokenKind::Fun, + "if" => TokenKind::If, + "nil" => TokenKind::Nil, + "or" => TokenKind::Or, + "print" => TokenKind::Print, + "return" => TokenKind::Return, + "super" => TokenKind::Super, + "this" => TokenKind::This, + "true" => TokenKind::True, + "var" => TokenKind::Var, + "while" => TokenKind::While, + _ => TokenKind::Identifier(ident), + }; + + self.add_token(token_kind); + } + fn scan_tokens(mut self) -> Vec<Token<'a>> { while !self.is_at_end() { self.start = self.current; self.scan_token(); } + self.add_token(TokenKind::Eof); return self.tokens; } } |