blob: 1c1dd6f42ff6a4bd1180f8e93e4999f68c4556ab (
plain) (
blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
|
use std::env;
use std::fs;
use std::io;
use std::io::Write;
use std::process;
mod errors;
mod parser;
mod scanner;
mod treewalk;
fn main() {
let mut args = env::args();
if args.len() > 2 {
println!("Usage: rlox [script]");
process::exit(1);
} else if let Some(file) = args.nth(1) {
run_file(&file);
} else {
run_prompt();
}
}
// Run Lox code from a file and print results to stdout
fn run_file(file: &str) {
let contents = fs::read_to_string(file).expect("failed to read the input file");
let mut lox = treewalk::interpreter::Interpreter::create();
run(&mut lox, &contents);
}
// Evaluate Lox code interactively in a shitty REPL.
fn run_prompt() {
let mut line = String::new();
let mut lox = treewalk::interpreter::Interpreter::create();
loop {
print!("> ");
io::stdout().flush().unwrap();
io::stdin()
.read_line(&mut line)
.expect("failed to read user input");
run(&mut lox, &line);
line.clear();
}
}
fn run(lox: &mut treewalk::interpreter::Interpreter, code: &str) {
let chars: Vec<char> = code.chars().collect();
let result = scanner::scan(&chars)
.and_then(|tokens| parser::parse(tokens))
.and_then(|program| lox.interpret(program).map_err(|e| vec![e]));
if let Err(errors) = result {
report_errors(errors);
}
}
fn report_errors(errors: Vec<errors::Error>) {
for error in errors {
errors::report(&error);
}
}
|