fix nat_binop abusing a rustc bug

source/framework/vire/compiler/nat.rs

@@ -2,10 +2,10 @@ use super::*;
 use blonkus_ma::nat_call;
 
 macro_rules! nat_binop {
-	( $id:literal , $name:ident , $op:expr ) => {
+	( $id:literal , $name:ident , $op:tt ) => {
 		#[nat_call($id, (i64) |i64, i64| -> i64)]
 		fn $name(x: i64, y: i64) -> i64 {
-			$op
+			x $op y
 		}
 	};
 }
@@ -15,10 +15,10 @@ fn dbgi(n: i64) {
 	eprintln!("{}", n);
 }
 
-nat_binop!("i+", addi, x + y);
-nat_binop!("i-", subi, x - y);
-nat_binop!("i*", muli, x * y);
-nat_binop!("i/", divi, x / y);
-nat_binop!("i%", remi, x % y);
+nat_binop!("i+", addi, +);
+nat_binop!("i-", subi, -);
+nat_binop!("i*", muli, *);
+nat_binop!("i/", divi, /);
+nat_binop!("i%", remi, %);
 
 // EOF