input function

src/sym.rs

@@ -101,10 +101,11 @@ impl SymTable {
          *   * sym is not in self
          *   * sym has a newer generation than the entry in self
          */
+        let tmp = self.1;
         for i in other.iter() {
             self.0.entry(i.0.to_string())
                 .and_modify(|inner: &mut Symbol| {
-                    if inner.__generation < i.1.__generation {
+                    if tmp < i.1.__generation {
                         inner.__generation = i.1.__generation;
                         inner.value = i.1.value.clone();
                         inner.args = i.1.args.clone();