Add Dynamic::UNIT.

RELEASES.md

@@ -10,6 +10,12 @@ New features
 ------------
 
 * `switch` statement.
+* `Engine::register_module` to register a module as a sub-module in the global namespace.
+
+Enhancements
+------------
+
+* New constant `Dynamic::UNIT`.
 
 
 Version 0.19.5

doc/src/engine/custom-op.md

@@ -94,7 +94,7 @@ The following _precedence table_ shows the built-in precedence of standard Rhai
 | ------------------- | :-------------------------------------------------------------------------------------: | :----------------: |
 | Assignments         | `=`, `+=`, `-=`, `*=`, `/=`, `~=`, `%=`,<br/>`<<=`, `>>=`, `&=`, <code>\|=</code>, `^=` |         0          |
 | Logic and bit masks |                        <code>\|\|</code>,  <code>\|</code>, `^`                         |         30         |
-| Logic and bit masks |                                        `&`, `&&`                                        |         60         |
+| Logic and bit masks |                                        `&&`, `&`                                        |         60         |
 | Comparisons         |                                       `==`, `!=`                                        |         90         |
 |                     |                                          `in`                                           |        110         |
 | Comparisons         |                                  `>`, `>=`, `<`, `<=`                                   |        130         |

doc/src/engine/custom-syntax.md

@@ -216,7 +216,7 @@ fn implementation_func(
         }
     }
 
-    Ok(().into())
+    Ok(Dynamic::UNIT)
 }
 
 // Register the custom syntax (sample): exec |x| -> { x += 1 } while x < 0;

doc/src/patterns/control.md

@@ -118,7 +118,7 @@ engine.register_result_fn("bunny_set_speed", move |speed: i64|
         return Err("Bunny is not yet going!".into());
     }
 
-    Ok(().into())
+    Ok(Dynamic::UNIT)
 );
 ```
 

doc/src/patterns/events.md

@@ -137,7 +137,7 @@ impl Handler {
                             // Default implementation of 'update' event handler
                             self.scope.set_value("state2", SomeType::new(42));
                             // Turn function-not-found into a success
-                            Ok(().into())
+                            Ok(Dynamic::UNIT)
                         }
                         _ => Err(err.into())
                     })

doc/src/patterns/singleton.md

@@ -131,7 +131,7 @@ pub mod bunny_api {
             Err("Bunny is not yet going!".into())
         } else {
             b.borrow_mut().set_speed(speed);
-            Ok(().into())
+            Ok(Dynamic::UNIT)
         }
     }
     pub fn turn_left(bunny: &mut SharedBunny) {

doc/src/rust/packages/index.md

@@ -10,7 +10,7 @@ packages to be used.
 
 Packages typically contain Rust functions that are callable within a Rhai script.
 All functions registered in a package is loaded under the _global namespace_
-(i.e. they're available without module qualifiers).
+(i.e. they're available without namespace qualifiers).
 
 Once a package is created (e.g. via `Package::new`), it can be _shared_ (via `Package::get`)
 among multiple instances of [`Engine`], even across threads (under [`sync`]).

doc/src/rust/register-raw.md

@@ -45,7 +45,7 @@ engine.register_raw_fn(
 
         *x += y;                                            // perform the action
 
-        Ok(().into())                                       // must be 'Result<Dynamic, Box<EvalAltResult>>'
+        Ok(Dynamic::UNIT)                                       // must be 'Result<Dynamic, Box<EvalAltResult>>'
     }
 );
 

doc/src/safety/progress.md

@@ -37,7 +37,7 @@ wrapping this value.
 The termination token is commonly used to provide information on the _reason_ or _source_
 behind the termination decision.
 
-If the termination token is not needed, simply return `Some(().into())` to terminate the script
+If the termination token is not needed, simply return `Some(Dynamic::UNIT)` to terminate the script
 run with [`()`] as the token.
 
 

src/dynamic.rs

@@ -532,11 +532,13 @@ impl Clone for Dynamic {
 impl Default for Dynamic {
     #[inline(always)]
     fn default() -> Self {
-        Self(Union::Unit(()))
+        Self::UNIT
     }
 }
 
 impl Dynamic {
+    pub const UNIT: Dynamic = Self(Union::Unit(()));
+
     /// Create a `Dynamic` from any type.  A `Dynamic` value is simply returned as is.
     ///
     /// # Safety

src/fn_call.rs

@@ -651,7 +651,7 @@ impl Engine {
 
         let script = script.trim();
         if script.is_empty() {
-            return Ok(().into());
+            return Ok(Dynamic::UNIT);
         }
 
         // Check for stack overflow

src/packages/array_basic.rs

@@ -54,7 +54,7 @@ macro_rules! gen_array_functions {
                         list.resize(len as usize, Dynamic::from(item));
                     }
 
-                    Ok(().into())
+                    Ok(Dynamic::UNIT)
                 }
             }
         })* }
@@ -367,7 +367,7 @@ mod array_functions {
         list: &mut Array,
         reducer: FnPtr,
     ) -> Result<Dynamic, Box<EvalAltResult>> {
-        let mut result: Dynamic = ().into();
+        let mut result: Dynamic = Dynamic::UNIT;
 
         for (i, item) in list.iter().enumerate() {
             result = reducer
@@ -434,7 +434,7 @@ mod array_functions {
         list: &mut Array,
         reducer: FnPtr,
     ) -> Result<Dynamic, Box<EvalAltResult>> {
-        let mut result: Dynamic = ().into();
+        let mut result: Dynamic = Dynamic::UNIT;
 
         for (i, item) in list.iter().enumerate().rev() {
             result = reducer
@@ -529,7 +529,7 @@ mod array_functions {
                 })
         });
 
-        Ok(().into())
+        Ok(Dynamic::UNIT)
     }
     #[rhai_fn(return_raw)]
     pub fn drain(

src/packages/string_more.rs

@@ -284,7 +284,7 @@ mod string_functions {
             }
         }
 
-        Ok(().into())
+        Ok(Dynamic::UNIT)
     }
     #[rhai_fn(name = "pad", return_raw)]
     pub fn pad_with_string(
@@ -328,7 +328,7 @@ mod string_functions {
             }
         }
 
-        Ok(().into())
+        Ok(Dynamic::UNIT)
     }
 
     #[cfg(not(feature = "no_index"))]

src/packages/time_basic.rs

@@ -150,7 +150,7 @@ mod time_functions {
         #[rhai_fn(return_raw, name = "+=")]
         pub fn add_assign(x: &mut Instant, seconds: FLOAT) -> Result<Dynamic, Box<EvalAltResult>> {
             *x = add_impl(*x, seconds)?;
-            Ok(().into())
+            Ok(Dynamic::UNIT)
         }
         #[rhai_fn(return_raw, name = "-")]
         pub fn subtract(x: Instant, seconds: FLOAT) -> Result<Dynamic, Box<EvalAltResult>> {
@@ -162,7 +162,7 @@ mod time_functions {
             seconds: FLOAT,
         ) -> Result<Dynamic, Box<EvalAltResult>> {
             *x = subtract_impl(*x, seconds)?;
-            Ok(().into())
+            Ok(Dynamic::UNIT)
         }
     }
 
@@ -204,7 +204,7 @@ mod time_functions {
     #[rhai_fn(return_raw, name = "+=")]
     pub fn add_assign(x: &mut Instant, seconds: INT) -> Result<Dynamic, Box<EvalAltResult>> {
         *x = add_impl(*x, seconds)?;
-        Ok(().into())
+        Ok(Dynamic::UNIT)
     }
     #[rhai_fn(return_raw, name = "-")]
     pub fn subtract(x: Instant, seconds: INT) -> Result<Dynamic, Box<EvalAltResult>> {
@@ -213,7 +213,7 @@ mod time_functions {
     #[rhai_fn(return_raw, name = "-=")]
     pub fn subtract_assign(x: &mut Instant, seconds: INT) -> Result<Dynamic, Box<EvalAltResult>> {
         *x = subtract_impl(*x, seconds)?;
-        Ok(().into())
+        Ok(Dynamic::UNIT)
     }
 
     #[rhai_fn(name = "==")]

src/parser.rs

@@ -957,7 +957,7 @@ fn parse_primary(
             let var_name_def = IdentX::new(state.get_interned_string(s), settings.pos);
             Expr::Variable(Box::new((None, None, 0, var_name_def)))
         }
-        // Module qualification
+        // Namespace qualification
         #[cfg(not(feature = "no_module"))]
         Token::Identifier(s) if *next_token == Token::DoubleColon => {
             // Once the identifier consumed we must enable next variables capturing

src/serde_impl/ser.rs

@@ -247,7 +247,7 @@ impl Serializer for &mut DynamicSerializer {
     }
 
     fn serialize_none(self) -> Result<Self::Ok, Box<EvalAltResult>> {
-        Ok(().into())
+        Ok(Dynamic::UNIT)
     }
 
     fn serialize_some<T: ?Sized + Serialize>(
@@ -258,7 +258,7 @@ impl Serializer for &mut DynamicSerializer {
     }
 
     fn serialize_unit(self) -> Result<Self::Ok, Box<EvalAltResult>> {
-        Ok(().into())
+        Ok(Dynamic::UNIT)
     }
 
     fn serialize_unit_struct(self, _name: &'static str) -> Result<Self::Ok, Box<EvalAltResult>> {

tests/syntax.rs

@@ -1,4 +1,4 @@
-use rhai::{Engine, EvalAltResult, LexError, ParseError, ParseErrorType, INT, NO_POS};
+use rhai::{Dynamic, Engine, EvalAltResult, LexError, ParseError, ParseErrorType, INT, NO_POS};
 
 #[test]
 fn test_custom_syntax() -> Result<(), Box<EvalAltResult>> {
@@ -48,7 +48,7 @@ fn test_custom_syntax() -> Result<(), Box<EvalAltResult>> {
                 }
             }
 
-            Ok(().into())
+            Ok(Dynamic::UNIT)
         },
     )?;
 
@@ -65,7 +65,7 @@ fn test_custom_syntax() -> Result<(), Box<EvalAltResult>> {
     // The first symbol must be an identifier
     assert_eq!(
         *engine
-            .register_custom_syntax(&["!"], 0, |_, _| Ok(().into()))
+            .register_custom_syntax(&["!"], 0, |_, _| Ok(Dynamic::UNIT))
             .expect_err("should error")
             .0,
         ParseErrorType::BadInput(LexError::ImproperSymbol(