55 lines
1.7 KiB
Rust
55 lines
1.7 KiB
Rust
use rustyline::Editor;
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use ablescript::interpret::ExecEnv;
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use ablescript::parser::Parser;
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pub fn repl(ast_print: bool) {
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let mut rl = Editor::<()>::new();
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let mut env = ExecEnv::new();
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loop {
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let readline = rl.readline(":: ");
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match readline {
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Ok(line) => {
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// NOTE(Alex): `readline()` leaves a newline at the
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// end of the string if stdin is connected to a file
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// or unsupported terminal; this can interfere with
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// error printing.
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rl.add_history_entry(&line);
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let line = line.trim_end();
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if line == "exit" {
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println!("bye");
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break;
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}
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let mut parser = Parser::new(line);
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let value = parser.init().and_then(|ast| {
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if ast_print {
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println!("{:#?}", &ast);
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}
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env.eval_stmts(&ast)
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});
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if let Err(e) = value {
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println!("{}", e);
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println!(" | {}", line);
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println!(
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" {}{}",
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" ".repeat(e.span.start),
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"^".repeat((e.span.end - e.span.start).max(1))
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);
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}
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}
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Err(rustyline::error::ReadlineError::Eof) => {
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println!("bye");
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break;
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}
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Err(rustyline::error::ReadlineError::Interrupted) => (),
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Err(e) => {
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println!("Error: {:?}", e);
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break;
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}
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}
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}
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}
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