rebel-lang: replace eval-string example with simple REPL

2 files changed, 29 insertions, 51 deletions

diff --git a/crates/rebel-lang/Cargo.toml b/crates/rebel-lang/Cargo.toml
index 44183be..0c2f684 100644
--- a/crates/rebel-lang/Cargo.toml
+++ b/crates/rebel-lang/Cargo.toml
@@ -15,3 +15,4 @@ enum-kinds = "0.5.1"
 
 [dev-dependencies]
 clap = { version = "4.0.0", features = ["derive"] }
+rustyline = "14.0.0"
diff --git a/crates/rebel-lang/examples/eval-string.rs b/crates/rebel-lang/examples/repl.rs
index a9c0b01..0163c6b 100644
--- a/crates/rebel-lang/examples/eval-string.rs
+++ b/crates/rebel-lang/examples/repl.rs
@@ -1,7 +1,3 @@
-use std::{fmt::Debug, process, time::Instant};
-
-use clap::Parser;
-
 use rebel_lang::{
 	func::{Func, FuncDef, FuncType},
 	typing::{ArrayLen, Type, TypeFamily},
@@ -9,11 +5,6 @@ use rebel_lang::{
 };
 use rebel_parse::{recipe, tokenize};
 
-#[derive(Clone, Debug, Parser)]
-struct Opts {
-	input: String,
-}
-
 fn intrinsic_array_len(params: &[Value]) -> Result<Value> {
 	assert!(params.len() == 1);
 	let Value::Array(array) = &params[0] else {
@@ -31,36 +22,7 @@ fn intrinsic_string_len(params: &[Value]) -> Result<Value> {
 	))
 }
 
-fn main() {
-	let opts: Opts = Opts::parse();
-	let input = opts.input.trim();
-
-	let start = Instant::now();
-	let result = tokenize::token_stream(input);
-	let dur = Instant::now().duration_since(start);
-	println!("Tokenization took {} µs", dur.as_micros());
-
-	let tokens = match result {
-		Ok(value) => value,
-		Err(err) => {
-			println!("{err}");
-			process::exit(1);
-		}
-	};
-
-	let start = Instant::now();
-	let result = recipe::expr(&tokens);
-	let dur = Instant::now().duration_since(start);
-	println!("Parsing took {} µs", dur.as_micros());
-
-	let expr = match result {
-		Ok(value) => value,
-		Err(err) => {
-			println!("{err}");
-			process::exit(1);
-		}
-	};
-
+fn main() -> rustyline::Result<()> {
 	let mut ctx = Context::default();
 
 	ctx.methods.entry(TypeFamily::Array).or_default().insert(
@@ -84,18 +46,33 @@ fn main() {
 		},
 	);
 
-	let start = Instant::now();
-	let result = ctx.eval(&expr);
-	let dur = Instant::now().duration_since(start);
-	println!("Eval took {} µs", dur.as_micros());
+	let mut rl = rustyline::DefaultEditor::new()?;
 
-	let value = match result {
-		Ok(value) => value,
-		Err(err) => {
-			println!("{err:?}");
-			process::exit(1);
-		}
-	};
+	while let Ok(line) = rl.readline("> ") {
+		rl.add_history_entry(line.as_str())?;
+		let tokens = match tokenize::token_stream(&line) {
+			Ok(value) => value,
+			Err(err) => {
+				println!("Tokenize error: {err}");
+				continue;
+			}
+		};
+		let expr = match recipe::expr(&tokens) {
+			Ok(value) => value,
+			Err(err) => {
+				println!("Parse error: {err}");
+				continue;
+			}
+		};
+		let value = match ctx.eval(&expr) {
+			Ok(value) => value,
+			Err(err) => {
+				println!("Eval error: {err:?}");
+				continue;
+			}
+		};
+		println!("{value}");
+	}
 
-	println!("{value}");
+	Ok(())
 }