clippy suggestions

src/interpreter/value.rs

@@ -27,7 +27,7 @@ impl Function {
         }
         self.args
             .iter()
-            .zip(args.into_iter())
+            .zip(args)
             .for_each(|(p, a)| ctx.assign(p.clone(), a));
         for i in self.ins.iter() {
             i.run(ctx, globals)?;
@@ -37,20 +37,22 @@ impl Function {
 
     pub fn from(fun: &Node<'_, '_>) -> Result<Function, Box<dyn Error>> {
         Ok(Function {
-            args: util::find_node(&fun, "arguments")
+            args: util::find_node(fun, "arguments")
                 .ok_or(MissingChild("call", "arguments"))?
                 .children()
                 .filter(Node::is_element)
-                .map(|n| n.attribute("name").and_then(|s| Some(String::from(s))))
+                .map(|n| n.attribute("name").map(String::from))
                 .collect::<Option<Vec<String>>>()
                 .ok_or(Unnamed("argument"))?,
             ins: Instruction::from_children(
-                util::find_node(&fun, "body").ok_or(MissingChild("call", "body"))?,
+                util::find_node(fun, "body").ok_or(MissingChild("call", "body"))?,
             )?,
         })
     }
 }
 
+type StdFn = fn(Vec<Value>) -> Result<Option<Value>, Box<dyn Error>>;
+
 #[derive(Clone, Debug)]
 pub enum Value {
     Integer(i64),
@@ -58,7 +60,7 @@ pub enum Value {
     String(String),
     Array(Rc<RefCell<Vec<Value>>>),
     Function(Function),
-    StdFunction(fn(Vec<Value>) -> Result<Option<Value>, Box<dyn Error>>),
+    StdFunction(StdFn),
 }
 
 impl Value {
@@ -66,7 +68,7 @@ impl Value {
         match self {
             Value::Integer(i) => *i != 0,
             Value::Real(f) => *f != 0.0,
-            Value::String(s) => s.len() != 0,
+            Value::String(s) => !s.is_empty(),
             Value::Array(v) => v.borrow().len() != 0,
             _ => true,
         }