diff --git a/tvix/eval/src/main.rs b/tvix/eval/src/main.rs index 41d9ed36b..0c4d08278 100644 --- a/tvix/eval/src/main.rs +++ b/tvix/eval/src/main.rs @@ -1,8 +1,6 @@ -use std::{ - env, fs, - io::{self, Write}, - mem, process, -}; +use std::{env, fs, path::PathBuf, process}; + +use rustyline::{error::ReadlineError, Editor}; fn main() { let mut args = env::args(); @@ -21,26 +19,58 @@ fn main() { fn run_file(file: &str) { let contents = fs::read_to_string(file).expect("failed to read the input file"); - run(contents); -} - -fn run_prompt() { - let mut line = String::new(); - - loop { - print!("> "); - io::stdout().flush().unwrap(); - io::stdin() - .read_line(&mut line) - .expect("failed to read user input"); - run(mem::take(&mut line)); - line.clear(); - } -} - -fn run(code: String) { - match tvix_eval::interpret(&code) { + match tvix_eval::interpret(&contents) { Ok(result) => println!("=> {} :: {}", result, result.type_of()), Err(err) => eprintln!("{}", err), } } + +fn state_dir() -> Option { + let mut path = dirs::data_dir(); + path.as_mut().map(|p| p.push("tvix")); + path +} + +fn run_prompt() { + let mut rl = Editor::<()>::new().expect("should be able to launch rustyline"); + + let history_path = match state_dir() { + Some(mut path) => { + path.push("history.txt"); + rl.load_history(&path).ok(); + + Some(path) + } + + None => None, + }; + + loop { + let readline = rl.readline("tvix-repl> "); + match readline { + Ok(line) => { + if line.is_empty() { + continue; + } + + match tvix_eval::interpret(&line) { + Ok(result) => { + println!("=> {} :: {}", result, result.type_of()); + rl.add_history_entry(line); + } + Err(err) => println!("{}", err), + } + } + Err(ReadlineError::Interrupted) | Err(ReadlineError::Eof) => break, + + Err(err) => { + eprintln!("error: {}", err); + break; + } + } + } + + if let Some(path) = history_path { + rl.save_history(&path).unwrap(); + } +}