diff --git a/bip/src/bp.rs b/bip/src/bp.rs
index e66119a..310dd00 100644
--- a/bip/src/bp.rs
+++ b/bip/src/bp.rs
@@ -101,6 +101,10 @@ impl Writer {
         self.buf.push(c);
     }
 
+    fn write_op(&mut self, op: Op) {
+        self.write(Op::encode(op));
+    }
+
     fn write_const(&mut self, c: u64) -> Result<()> {
         let width = width!(c) as u8;
 
@@ -125,10 +129,6 @@ impl Writer {
         self.write(0x00);
     }
 
-    fn write_op(&mut self, op: Op) {
-        self.write(Op::encode(op));
-    }
-
     fn parse_data_type(&mut self, node: &Node) -> Vec<String> {
         let mut bind_table = vec![];