Refine function call parameters size.

src/engine.rs

@@ -37,6 +37,7 @@ use crate::stdlib::{
     collections::{HashMap, HashSet},
     fmt, format,
     iter::{empty, once},
+    num::NonZeroUsize,
     ops::DerefMut,
     string::{String, ToString},
     vec::Vec,
@@ -250,8 +251,8 @@ impl<'a> Target<'a> {
             Self::LockGuard(_) => (),
             #[cfg(not(feature = "no_index"))]
             Self::StringChar(_, _, ch) => {
-                let new_val = ch.clone();
+                let char_value = ch.clone();
-                self.set_value((new_val, Position::none()), Position::none())
+                self.set_value((char_value, Position::none()), Position::none())
                     .unwrap();
             }
         }
@@ -284,10 +285,9 @@ impl<'a> Target<'a> {
                 })?;
 
                 let mut chars = s.chars().collect::<StaticVec<_>>();
-                let ch = chars[*index];
 
                 // See if changed - if so, update the String
-                if ch != new_ch {
+                if chars[*index] != new_ch {
                     chars[*index] = new_ch;
                     *s = chars.iter().collect::<String>().into();
                 }
@@ -520,13 +520,13 @@ pub fn search_imports<'s>(
 
     // Qualified - check if the root module is directly indexed
     let index = if state.always_search {
-        None
+        0
     } else {
-        modules.index()
+        modules.index().map_or(0, NonZeroUsize::get)
     };
 
-    Ok(if let Some(index) = index {
+    Ok(if index > 0 {
-        let offset = mods.len() - index.get();
+        let offset = mods.len() - index;
         &mods.get(offset).unwrap().1
     } else {
         mods.iter()
@@ -548,13 +548,13 @@ pub fn search_imports_mut<'s>(
 
     // Qualified - check if the root module is directly indexed
     let index = if state.always_search {
-        None
+        0
     } else {
-        modules.index()
+        modules.index().map_or(0, NonZeroUsize::get)
     };
 
-    Ok(if let Some(index) = index {
+    Ok(if index > 0 {
-        let offset = mods.len() - index.get();
+        let offset = mods.len() - index;
         &mut mods.get_mut(offset).unwrap().1
     } else {
         mods.iter_mut()
@@ -684,19 +684,15 @@ impl Engine {
                 // Qualified variable
                 ((name, pos), Some(modules), hash_var, _) => {
                     let module = search_imports_mut(mods, state, modules)?;
-                    let target =
+                    let target = module.get_qualified_var_mut(*hash_var).map_err(|mut err| {
-                        module
+                        match *err {
-                            .get_qualified_var_mut(*hash_var)
+                            EvalAltResult::ErrorVariableNotFound(ref mut err_name, _) => {
-                            .map_err(|err| match *err {
+                                *err_name = format!("{}{}", modules, name);
-                                EvalAltResult::ErrorVariableNotFound(_, _) => {
+                            }
-                                    EvalAltResult::ErrorVariableNotFound(
+                            _ => (),
-                                        format!("{}{}", modules, name),
+                        }
-                                        *pos,
+                        err.fill_position(*pos)
-                                    )
+                    })?;
-                                    .into()
-                                }
-                                _ => err.fill_position(*pos),
-                            })?;
 
                     // Module variables are constant
                     Ok((target.into(), name, ScopeEntryType::Constant, *pos))
@@ -733,7 +729,11 @@ impl Engine {
         }
 
         // Check if it is directly indexed
-        let index = if state.always_search { None } else { *index };
+        let index = if state.always_search {
+            0
+        } else {
+            index.map_or(0, NonZeroUsize::get)
+        };
 
         // Check the variable resolver, if any
         if let Some(ref resolve_var) = self.resolve_var {
@@ -745,15 +745,15 @@ impl Engine {
                 this_ptr,
                 level: 0,
             };
-            if let Some(result) = resolve_var(name, index.map_or(0, |v| v.get()), scope, &context)
+            if let Some(result) =
-                .map_err(|err| err.fill_position(*pos))?
+                resolve_var(name, index, scope, &context).map_err(|err| err.fill_position(*pos))?
             {
                 return Ok((result.into(), name, ScopeEntryType::Constant, *pos));
             }
         }
 
-        let index = if let Some(index) = index {
+        let index = if index > 0 {
-            scope.len() - index.get()
+            scope.len() - index
         } else {
             // Find the variable in the scope
             scope

src/fn_call.rs

@@ -50,10 +50,6 @@ use crate::stdlib::{
     vec::Vec,
 };
 
-#[cfg(not(feature = "no_closure"))]
-#[cfg(not(feature = "no_function"))]
-use crate::stdlib::{collections::HashSet, string::String};
-
 #[cfg(feature = "no_std")]
 #[cfg(not(feature = "no_float"))]
 use num_traits::float::Float;
@@ -146,29 +142,6 @@ impl Drop for ArgBackup<'_> {
     }
 }
 
-// Add captured variables into scope
-#[cfg(not(feature = "no_closure"))]
-#[cfg(not(feature = "no_function"))]
-fn add_captured_variables_into_scope<'s>(
-    externals: &HashSet<String>,
-    captured: Scope<'s>,
-    scope: &mut Scope<'s>,
-) {
-    captured
-        .into_iter()
-        .filter(|ScopeEntry { name, .. }| externals.contains(name.as_ref()))
-        .for_each(
-            |ScopeEntry {
-                 name, typ, value, ..
-             }| {
-                match typ {
-                    ScopeEntryType::Normal => scope.push(name, value),
-                    ScopeEntryType::Constant => scope.push_constant(name, value),
-                };
-            },
-        );
-}
-
 #[inline(always)]
 pub fn ensure_no_data_race(
     fn_name: &str,
@@ -483,6 +456,8 @@ impl Engine {
     /// Perform an actual function call, native Rust or scripted, taking care of special functions.
     /// Position in `EvalAltResult` is `None` and must be set afterwards.
     ///
+    /// Capture `Scope` is consumed by this function.
+    ///
     /// ## WARNING
     ///
     /// Function call arguments may be _consumed_ when the function requires them to be passed by value.
@@ -498,7 +473,7 @@ impl Engine {
         is_ref: bool,
         _is_method: bool,
         pub_only: bool,
-        _capture: Option<Scope>,
+        _capture: Option<&mut Scope>, // `Scope` is consumed.
         def_val: &Option<Dynamic>,
         _level: usize,
     ) -> Result<(Dynamic, bool), Box<EvalAltResult>> {
@@ -574,10 +549,29 @@ impl Engine {
                     let scope = &mut Scope::new();
                     let mods = &mut Imports::new();
 
-                    // Add captured variables into scope
+                    // Move captured variables into scope
                     #[cfg(not(feature = "no_closure"))]
                     if let Some(captured) = _capture {
-                        add_captured_variables_into_scope(&func.externals, captured, scope);
+                        captured
+                            .iter_mut()
+                            .filter(|ScopeEntry { name, .. }| {
+                                func.externals.contains(name.as_ref())
+                            })
+                            .for_each(
+                                |ScopeEntry {
+                                     name, typ, value, ..
+                                 }| {
+                                    // Consume the scope values.
+                                    match typ {
+                                        ScopeEntryType::Normal => {
+                                            scope.push(name.clone(), mem::take(value))
+                                        }
+                                        ScopeEntryType::Constant => {
+                                            scope.push_constant(name.clone(), mem::take(value))
+                                        }
+                                    };
+                                },
+                            );
                     }
 
                     let result = if _is_method {
@@ -1019,11 +1013,13 @@ impl Engine {
         let mut arg_values: StaticVec<_>;
         let mut args: StaticVec<_>;
         let mut is_ref = false;
-        let capture = if cfg!(not(feature = "no_closure")) && capture && !scope.is_empty() {
+        let mut capture_scope = if cfg!(not(feature = "no_closure")) && capture && !scope.is_empty()
-            Some(scope.flatten_clone())
+        {
+            Some(scope.clone_visible())
         } else {
             None
         };
+        let capture = capture_scope.as_mut();
 
         if args_expr.is_empty() && curry.is_empty() {
             // No arguments
@@ -1189,20 +1185,12 @@ impl Engine {
                 let args = args.as_mut();
                 let func = f.get_fn_def();
 
-                let scope = &mut Scope::new();
+                let new_scope = &mut Scope::new();
                 let mods = &mut Imports::new();
 
-                // Add captured variables into scope
+                self.call_script_fn(
-                #[cfg(not(feature = "no_closure"))]
+                    new_scope, mods, state, lib, &mut None, name, func, args, level,
-                if _capture && !scope.is_empty() {
+                )
-                    add_captured_variables_into_scope(
-                        &func.externals,
-                        scope.flatten_clone(),
-                        scope,
-                    );
-                }
-
-                self.call_script_fn(scope, mods, state, lib, &mut None, name, func, args, level)
             }
             Some(f) if f.is_plugin_fn() => f.get_plugin_fn().call(args.as_mut()),
             Some(f) if f.is_native() => {

src/scope.rs

@@ -420,7 +420,7 @@ impl<'a> Scope<'a> {
     /// Clone the Scope, keeping only the last instances of each variable name.
     /// Shadowed variables are omitted in the copy.
     #[inline]
-    pub(crate) fn flatten_clone(&self) -> Self {
+    pub(crate) fn clone_visible(&self) -> Self {
         let mut entries: Vec<Entry> = Default::default();
 
         self.0.iter().rev().for_each(|entry| {
@@ -488,6 +488,12 @@ impl<'a> Scope<'a> {
              }| { (name.as_ref(), typ.is_constant(), value) },
         )
     }
+
+    /// Get a mutable iterator to entries in the Scope.
+    #[inline(always)]
+    pub(crate) fn iter_mut(&mut self) -> impl Iterator<Item = &mut Entry<'a>> {
+        self.0.iter_mut()
+    }
 }
 
 impl<'a, K: Into<Cow<'a, str>>> iter::Extend<(K, EntryType, Dynamic)> for Scope<'a> {