68 lines
1.7 KiB
Rust
68 lines
1.7 KiB
Rust
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use crate::tokens::Token;
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use std::sync::Arc;
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pub struct Lexer {
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/// GLSL source
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pub input: Vec<char>,
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/// Position in source
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pub position: usize,
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/// [`char`] under position
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pub current_char: Option<char>,
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}
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impl Lexer {
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pub fn new(input: &str) -> Self {
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let mut lexer = Lexer {
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input: input.chars().collect(),
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position: 0,
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current_char: None,
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};
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lexer.current_char = if lexer.position < lexer.input.len() {
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Some(lexer.input[lexer.position])
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} else {
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None
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};
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lexer
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}
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fn advance(&mut self) {
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self.position += 1;
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self.current_char = if self.position < self.input.len() {
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Some(self.input[self.position])
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} else {
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None
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};
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}
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fn peek(&self) -> Option<char> {
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if self.position + 1 < self.input.len() {
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Some(self.input[self.position + 1])
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} else {
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None
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}
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}
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/// Parses the source given the [`Lexer`] upon initialization and returns a vector of [`Token`].
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/// # Example:
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/// ```
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/// use glsl_lexer::*;
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/// let source = r#"
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/// #version 440
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/// uniform float time;
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/// void main() {
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/// gl_FragColor = vec4(1.0, 0.5, 0.2, 1.0);
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/// }
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/// "#;
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/// let mut lexer = glsl_lexer::Lexer::new(&source);
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/// let tokens = lexer.get_tokens();
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/// dbg!("{}", tokens);
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///```
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// We are using Arc<[Token]> as return type for cheaper cloning of the returned value
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fn get_tokens(&mut self) -> Arc<[Token]> {
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let mut tokens: Vec<Token> = Vec::new();
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tokens.into()
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}
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fn match_token(&self, ) -> Token {}
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}
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