Added group parsing

src/main.rs

@@ -0,0 +1,100 @@
+use std::io;
+use std::io::Write;
+//use std::io::Read;
+use std::sync::Arc;
+use std::sync::atomic::{AtomicBool, Ordering};
+
+use termcolor::{
+	Color,
+	ColorChoice,
+	ColorSpec,
+	StandardStream,
+	WriteColor
+};
+
+pub mod tokenize;
+
+const PROMPT_PREFIX: &str = "==> ";
+
+/// Show a prompt and save trimmed input to `input`.
+///
+/// # Arguments:
+/// 
+/// * `stdout`: Where we should write the prompt
+/// * `input`: Where we should save user input
+///
+/// # Example usage:
+/// ```
+/// let mut input = String::new();
+/// prompt(&mut stdout, &mut input)?;
+/// ```
+fn prompt(
+	stdout: &mut StandardStream,
+	input: &mut String
+) -> Result<(), std::io::Error> {
+
+	// Print colored prompt prefix
+	stdout.set_color(ColorSpec::new().set_fg(Some(Color::Blue)))?;
+	write!(*stdout, "{PROMPT_PREFIX}")?;
+	stdout.reset()?;  // reset colors
+	stdout.flush()?;  // flush, we didn't print a full line yet.
+
+	// Ask for input
+	io::stdin().read_line(input)?;
+
+	// If this input doesn't end with a newline,
+	// the user terminated this prompt with ctrl-d.
+	// Add a newline to keep spacing consistent,
+	// and clear the input.
+	if match input.chars().last() {
+			Some(val) => val != '\n',
+			None => true
+	} {
+		write!(*stdout, "\n")?;
+		input.clear();
+	} else {
+		(*input) = input.trim().to_string();
+	}
+
+	Ok(())
+}
+
+fn main() -> Result<(), std::io::Error> {
+
+	let mut stdout = StandardStream::stdout(ColorChoice::Always);
+
+	let term = Arc::new(AtomicBool::new(false));
+	signal_hook::flag::register(signal_hook::consts::SIGINT, Arc::clone(&term))?;
+	while !term.load(Ordering::Relaxed) {
+		let mut input = String::with_capacity(64);
+		prompt(&mut stdout, &mut input).expect("Could not show prompt");
+		let input = input;
+
+		// Ignore empty input
+		if input == "" {
+			stdout.flush()?;
+			continue;
+		}
+
+		// Tokenize input.
+		// Fail if we encounter invalid characters.
+		let tokens = match tokenize::tokenize(&input) {
+			Ok(v) => v,
+			Err(_) => {
+				continue;
+			}
+		};
+
+
+		stdout.set_color(ColorSpec::new().set_fg(Some(Color::Green)))?;
+		write!(stdout, "\n  => ")?;
+		stdout.reset()?;
+		write!(stdout, "Got {input}\n\n\n")?;
+
+		writeln!(stdout, "Tokenized: {tokens:#?}")?;
+
+	}
+
+	writeln!(stdout, "Exiting.")?;
+	Ok(())
+}