57 lines
1.4 KiB
Rust
57 lines
1.4 KiB
Rust
use super::preprocessor::preprocess;
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use super::token::Token;
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pub struct Lexer {
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code: String,
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pos: usize,
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current: Option<char>,
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}
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impl Lexer {
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pub fn new(code: String) -> Lexer {
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Lexer {
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code: code.clone(),
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pos: 0,
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current: code.chars().nth(0),
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}
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}
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pub fn next(&mut self) {
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self.pos += 1;
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self.current = if self.pos < self.code.len() {
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self.code.chars().nth(self.pos)
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} else {
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None
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};
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}
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pub fn tokenize(&mut self) {
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let mut tokens: Vec<Token> = vec![];
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self.code = preprocess(self.code.clone());
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loop {
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let token: Option<Token> = match self.current {
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Some('+') => Some(Token::ADD),
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Some('-') => Some(Token::SUBTRACT),
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Some('*') => Some(Token::MULTIPLY),
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Some('/') => Some(Token::DIVIDE),
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Some('(') => Some(Token::LBRACK),
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Some(')') => Some(Token::RBRACK),
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Some(' ') => None,
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Some('\n') => None,
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None => break,
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Some(_) => None,
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};
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match token {
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Some(token) => {
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tokens.push(token);
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self.next();
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},
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None => self.next(),
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}
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}
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println!("{:?}", tokens);
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}
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}
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