1 files changed, 78 insertions, 0 deletions
diff --git a/crates/rebel-lang/examples/repl.rs b/crates/rebel-lang/examples/repl.rs
new file mode 100644
index 0000000..0163c6b
--- /dev/null
+++ b/crates/rebel-lang/examples/repl.rs
@@ -0,0 +1,78 @@
+use rebel_lang::{
+	func::{Func, FuncDef, FuncType},
+	typing::{ArrayLen, Type, TypeFamily},
+	value::{Context, EvalError, Result, Value},
+};
+use rebel_parse::{recipe, tokenize};
+
+fn intrinsic_array_len(params: &[Value]) -> Result<Value> {
+	assert!(params.len() == 1);
+	let Value::Array(array) = &params[0] else {
+		panic!();
+	};
+	Ok(Value::Integer(array.len().try_into().or(Err(EvalError))?))
+}
+fn intrinsic_string_len(params: &[Value]) -> Result<Value> {
+	assert!(params.len() == 1);
+	let Value::Str(string) = &params[0] else {
+		panic!();
+	};
+	Ok(Value::Integer(
+		string.chars().count().try_into().or(Err(EvalError))?,
+	))
+}
+
+fn main() -> rustyline::Result<()> {
+	let mut ctx = Context::default();
+
+	ctx.methods.entry(TypeFamily::Array).or_default().insert(
+		"len",
+		Func {
+			typ: FuncType {
+				params: vec![Type::Array(Box::new(Type::Free), ArrayLen::Dynamic)],
+				ret: Type::Int,
+			},
+			def: FuncDef::Intrinsic(intrinsic_array_len),
+		},
+	);
+	ctx.methods.entry(TypeFamily::Str).or_default().insert(
+		"len",
+		Func {
+			typ: FuncType {
+				params: vec![Type::Str],
+				ret: Type::Int,
+			},
+			def: FuncDef::Intrinsic(intrinsic_string_len),
+		},
+	);
+
+	let mut rl = rustyline::DefaultEditor::new()?;
+
+	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}");
+	}
+
+	Ok(())
+}