Merge in function pointer arguments.

src/module/mod.rs

@@ -3,7 +3,7 @@
 use crate::any::{Dynamic, Variant};
 use crate::calc_fn_hash;
 use crate::engine::Engine;
-use crate::fn_native::{CallableFunction, FnCallArgs, IteratorFn, SendSync};
+use crate::fn_native::{CallableFunction, FnCallArgs, FnPtr, IteratorFn, SendSync};
 use crate::fn_register::by_value as cast_arg;
 use crate::parser::{FnAccess, FnAccess::Public};
 use crate::result::EvalAltResult;
@@ -1217,11 +1217,16 @@ impl Module {
     ///
     /// ### `private_namespace` parameter
     ///
-    /// If `true`, the entire `AST` is encapsulated into each function as a private namespace,
-    /// allowing functions to cross-call each other.
+    /// * If `true`, the entire `AST` is encapsulated into each function as a private namespace,
+    ///   allowing functions to cross-call each other.  Functions are searched in the module's
+    ///   private namespace, and the global namespace cannot be accessed.
     ///
-    /// If `false`, each function is registered independently and cannot cross-call
-    /// each other. Functions are searched in the global namespace.
+    ///   Under this scenario, if any argument is a function pointer, then the function referred
+    ///   to by the function pointer is also _merged_ into the module's private namespace before
+    ///   the function call, so passing simple closures to functions work as expected.
+    ///
+    /// * If `false`, each function is registered independently and cannot cross-call
+    ///   each other. Functions are searched in the global namespace.
     ///
     /// # Examples
     ///
@@ -1277,11 +1282,32 @@ impl Module {
                     module.set_raw_fn_as_scripted(
                         name,
                         num_args,
-                        move |engine: &Engine, _, args: &mut [&mut Dynamic]| {
+                        move |engine: &Engine, lib: &Module, args: &mut [&mut Dynamic]| {
+                            // Get anonymous functions
+                            let anon_fns: StaticVec<_> = args
+                                .iter()
+                                .filter(|&arg| arg.is::<FnPtr>())
+                                .map(|arg| arg.read_lock::<FnPtr>().unwrap().get_fn_name().clone())
+                                .collect();
+
+                            let mut lib_merged;
+
+                            let call_lib = if anon_fns.is_empty() {
+                                // No anonymous functions - just pass the AST through
+                                &ast_lib
+                            } else {
+                                // If there are anonymous functions, merge them in
+                                lib_merged = ast_lib.clone();
+                                lib_merged.merge_filtered(&lib, &mut |_, name, _| {
+                                    anon_fns.iter().find(|s| s.as_str() == name).is_some()
+                                });
+                                &lib_merged
+                            };
+
                             engine
                                 .call_fn_dynamic_raw(
                                     &mut Scope::new(),
-                                    &ast_lib,
+                                    call_lib,
                                     &fn_name,
                                     &mut None,
                                     args,

src/module/resolvers/stat.rs

@@ -49,8 +49,7 @@ impl StaticModuleResolver {
 
 impl StaticModuleResolver {
     /// Add a module keyed by its path.
-    pub fn insert<S: Into<String>>(&mut self, path: S, mut module: Module) {
-        module.index_all_sub_modules();
+    pub fn insert<S: Into<String>>(&mut self, path: S, module: Module) {
         self.0.insert(path.into(), module);
     }
     /// Remove a module given its path.