Add std.exit

src/runtime/lib/exit.rs

@@ -0,0 +1,35 @@
+use std::convert::TryFrom;
+
+use gc::{Finalize, Trace};
+
+use super::{
+	CallContext,
+	NativeFun,
+	RustFun,
+	Panic,
+	Value,
+};
+
+
+inventory::submit!{ RustFun::from(Exit) }
+
+#[derive(Trace, Finalize)]
+struct Exit;
+
+impl NativeFun for Exit {
+	fn name(&self) -> &'static str { "std.exit" }
+
+	fn call(&self, context: CallContext) -> Result<Value, Panic> {
+		match context.args() {
+			[ val @ Value::Int(i) ] => {
+				let code = u8::try_from(*i)
+					.map_err(|_| Panic::value_error(val.copy(), "valid exit code", context.pos.copy()))?;
+
+				std::process::exit(code.into())
+			}
+
+			[ other ] => Err(Panic::type_error(other.copy(), "int", context.pos)),
+			args => Err(Panic::invalid_args(args.len() as u32, 1, context.pos))
+		}
+	}
+}