Better function parameter names.

src/optimize.rs

@@ -686,7 +686,7 @@ fn optimize_stmt(stmt: &mut Stmt, state: &mut OptimizerState, preserve_result: b
 }
 
 /// Optimize an [expression][Expr].
-fn optimize_expr(expr: &mut Expr, state: &mut OptimizerState, _chaining: bool) {
+fn optimize_expr(expr: &mut Expr, state: &mut OptimizerState, chaining: bool) {
     // These keywords are handled specially
     const DONT_EVAL_KEYWORDS: &[&str] = &[
         KEYWORD_PRINT, // side effects
@@ -694,6 +694,8 @@ fn optimize_expr(expr: &mut Expr, state: &mut OptimizerState, _chaining: bool) {
         KEYWORD_EVAL,  // arbitrary scripts
     ];
 
+    let _chaining = chaining;
+
     match expr {
         // {}
         Expr::Stmt(x) if x.is_empty() => { state.set_dirty(); *expr = Expr::Unit(x.position()) }
@@ -1061,12 +1063,14 @@ fn optimize_expr(expr: &mut Expr, state: &mut OptimizerState, _chaining: bool) {
 
 /// Optimize a block of [statements][Stmt] at top level.
 fn optimize_top_level(
-    mut statements: Vec<Stmt>,
+    statements: Vec<Stmt>,
     engine: &Engine,
     scope: &Scope,
     lib: &[&Module],
     optimization_level: OptimizationLevel,
 ) -> Vec<Stmt> {
+    let mut statements = statements;
+
     // If optimization level is None then skip optimizing
     if optimization_level == OptimizationLevel::None {
         statements.shrink_to_fit();
@@ -1093,8 +1097,8 @@ fn optimize_top_level(
 pub fn optimize_into_ast(
     engine: &Engine,
     scope: &Scope,
-    mut statements: Vec<Stmt>,
-    _functions: Vec<crate::Shared<crate::ast::ScriptFnDef>>,
+    statements: Vec<Stmt>,
+    functions: Vec<crate::Shared<crate::ast::ScriptFnDef>>,
     optimization_level: OptimizationLevel,
 ) -> AST {
     let level = if cfg!(feature = "no_optimize") {
@@ -1103,6 +1107,9 @@ pub fn optimize_into_ast(
         optimization_level
     };
 
+    let mut statements = statements;
+    let _functions = functions;
+
     #[cfg(not(feature = "no_function"))]
     let lib = {
         let mut module = Module::new();