20a6cfeee2
This removes the runtime dependency on a borrow into the program source code. It's not yet ideal because there are a lot of tokens where we really don't care about the lexeme, but this is what the book does and I am not going to change that. Change-Id: I888e18f98597766d6f725cbf9241e8eb2bd839e2 Reviewed-on: https://cl.tvl.fyi/c/depot/+/2394 Reviewed-by: tazjin <mail@tazj.in> Tested-by: BuildkiteCI
69 lines
1.7 KiB
Rust
69 lines
1.7 KiB
Rust
use std::env;
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use std::fs;
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use std::io;
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use std::io::Write;
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use std::process;
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mod errors;
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mod interpreter;
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mod parser;
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mod scanner;
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fn main() {
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let mut args = env::args();
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if args.len() > 2 {
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println!("Usage: rlox [script]");
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process::exit(1);
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} else if let Some(file) = args.nth(1) {
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run_file(&file);
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} else {
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run_prompt();
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}
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}
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// Run Lox code from a file and print results to stdout
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fn run_file(file: &str) {
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let contents = fs::read_to_string(file).expect("failed to read the input file");
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let mut lox = interpreter::Interpreter::create();
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run(&mut lox, &contents);
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}
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// Evaluate Lox code interactively in a shitty REPL.
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fn run_prompt() {
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let mut line = String::new();
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let mut lox = interpreter::Interpreter::create();
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loop {
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print!("> ");
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io::stdout().flush().unwrap();
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io::stdin()
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.read_line(&mut line)
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.expect("failed to read user input");
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run(&mut lox, &line);
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line.clear();
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}
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}
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fn run(lox: &mut interpreter::Interpreter, code: &str) {
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let chars: Vec<char> = code.chars().collect();
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match scanner::scan(&chars) {
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Ok(tokens) => match parser::parse(tokens) {
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Ok(program) => {
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println!("Program:\n{:?}", program);
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if let Err(err) = lox.interpret(&program) {
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println!("Error in program: {:?}", err);
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}
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}
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Err(errors) => report_errors(errors),
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},
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Err(errors) => report_errors(errors),
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}
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}
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fn report_errors(errors: Vec<errors::Error>) {
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for error in errors {
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errors::report(&error);
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}
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}
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