deelang/src/main.rs

71 lines
1.8 KiB
Rust

mod parser;
mod evaluator;
mod emitter;
use clap::Parser;
use std::io;
use std::io::prelude::*;
use std::fs::File;
use std::path::PathBuf;
#[derive(Parser, Debug)]
#[clap(author, version, about = "Interpreter for Deelang")]
struct Cli {
#[clap(help="Specify a file to run")]
file: Option<PathBuf>,
#[clap(short, long, help="Only parse, do not evaluate")]
parse: bool,
#[clap(short, long, help="Cross-compile to ECMAScript")]
ecmascript: bool,
#[clap(long, help="Only run the pre-processor")]
preprocess: bool,
}
fn repl(cli: &Cli) {
let mut global = evaluator::Env::global();
let mut toplevel = emitter::LexicalContext::toplevel();
let mut out = io::stdout();
loop {
let mut line = String::new();
io::stdin().read_line(&mut line).unwrap();
let tree = parser::parse_stmt(&line);
if cli.parse {
println!("{:#?}", tree);
} else if cli.ecmascript {
emitter::emit(&mut out, &tree, &mut toplevel).ok();
} else {
evaluator::eval(&tree, &mut global);
}
}
}
fn script(cli: &Cli) {
let mut file = File::open(cli.file.as_ref().unwrap()).expect("Could not read file");
let mut prgm = String::new();
file.read_to_string(&mut prgm).unwrap();
if cli.preprocess {
println!("{}", parser::preprocess(&prgm));
return;
}
let tree = parser::parse(&prgm);
if cli.parse {
println!("{:#?}", tree);
} else if cli.ecmascript {
let mut out = io::stdout();
emitter::emit_injector(&mut out).ok();
let mut toplevel = emitter::LexicalContext::toplevel();
emitter::emit_all(&mut out, &tree, &mut toplevel).ok();
} else {
todo!();
}
}
fn main() {
let cli = Cli::parse();
match cli.file {
None => repl(&cli),
Some(_) => script(&cli),
}
}