Implement namespaces chain.

src/optimize.rs

@@ -70,7 +70,7 @@ struct State<'a> {
     /// An `Engine` instance for eager function evaluation.
     engine: &'a Engine,
     /// Library of script-defined functions.
-    lib: &'a Module,
+    lib: &'a [&'a Module],
     /// Optimization level.
     optimization_level: OptimizationLevel,
 }
@@ -78,7 +78,7 @@ struct State<'a> {
 impl<'a> State<'a> {
     /// Create a new State.
     #[inline(always)]
-    pub fn new(engine: &'a Engine, lib: &'a Module, level: OptimizationLevel) -> Self {
+    pub fn new(engine: &'a Engine, lib: &'a [&'a Module], level: OptimizationLevel) -> Self {
         Self {
             changed: false,
             constants: vec![],
@@ -615,7 +615,7 @@ fn optimize_expr(expr: Expr, state: &mut State) -> Expr {
 
             // First search for script-defined functions (can override built-in)
             #[cfg(not(feature = "no_function"))]
-            let has_script_fn = state.lib.get_script_fn(name, args.len(), false).is_some();
+            let has_script_fn = state.lib.iter().any(|&m| m.get_script_fn(name, args.len(), false).is_some());
             #[cfg(feature = "no_function")]
             let has_script_fn = false;
 
@@ -686,7 +686,7 @@ fn optimize(
     statements: Vec<Stmt>,
     engine: &Engine,
     scope: &Scope,
-    lib: &Module,
+    lib: &[&Module],
     level: OptimizationLevel,
 ) -> Vec<Stmt> {
     // If optimization level is None then skip optimizing
@@ -837,7 +837,8 @@ pub fn optimize_into_ast(
                     let pos = fn_def.body.position();
 
                     // Optimize the function body
-                    let mut body = optimize(vec![fn_def.body], engine, &Scope::new(), &lib2, level);
+                    let mut body =
+                        optimize(vec![fn_def.body], engine, &Scope::new(), &[&lib2], level);
 
                     // {} -> Noop
                     fn_def.body = match body.pop().unwrap_or_else(|| Stmt::Noop(pos)) {
@@ -877,7 +878,7 @@ pub fn optimize_into_ast(
         match level {
             OptimizationLevel::None => statements,
             OptimizationLevel::Simple | OptimizationLevel::Full => {
-                optimize(statements, engine, &scope, &lib, level)
+                optimize(statements, engine, &scope, &[&lib], level)
             }
         },
         lib,