kjuulh/rhai
1
0
Fork 0
Code Issues 1 Pull Requests 1 Packages Projects Releases Wiki Activity

Implement index setters.

Browse Source
This commit is contained in:
Stephen Chung 2020-06-06 13:06:00 +08:00
parent 56eb659d5a
commit 5f40a1376a
6 changed files with 339 additions and 121 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

59
README.md
View File

@ -472,7 +472,7 @@ The follow packages are available:
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).
Once a package is created (e.g. via `new`), it can be _shared_ (via `get`) among multiple instances of [`Engine`],
even across threads (under the [`sync`] feature). Therefore, a package only has to be created _once_.
even across threads (under [`sync`]). Therefore, a package only has to be created _once_.
Packages are actually implemented as [modules], so they share a lot of behavior and characteristics.
The main difference is that a package loads under the _global_ namespace, while a module loads under its own
@ -572,7 +572,7 @@ if type_of(x) == "string" {
[`Dynamic`]: #dynamic-values
A `Dynamic` value can be _any_ type. However, under the [`sync`] feature, all types must be `Send + Sync`.
A `Dynamic` value can be _any_ type. However, under [`sync`], all types must be `Send + Sync`.
Because [`type_of()`] a `Dynamic` value returns the type of the actual value, it is usually used to perform type-specific
actions based on the actual value's type.
@ -975,8 +975,8 @@ let result = engine.eval::<i64>(
println!("result: {}", result); // prints 1
```
Under the [`no_object`] feature, however, the _method_ style of function calls
(i.e. calling a function as an object-method) is no longer supported.
Under [`no_object`], however, the _method_ style of function calls (i.e. calling a function as an object-method)
is no longer supported.
```rust
// Below is a syntax error under 'no_object' because 'clear' cannot be called in method style.
@ -999,8 +999,7 @@ let x = new_ts();
print(x.type_of()); // prints "Hello"
```
Getters and setters
-------------------
### Getters and setters
Similarly, custom types can expose members by registering a `get` and/or `set` function.
@ -1040,12 +1039,10 @@ let result = engine.eval::<String>(r#"let a = new_ts(); a.xyz = "42"; a.xyz"#)?;
println!("Answer: {}", result); // prints 42
```
Indexers
--------
### Indexers
Custom types can also expose an _indexer_ by registering an indexer function.
A custom type with an indexer function defined can use the bracket '`[]`' notation to get a property value
(but not update it - indexers are read-only).
```rust
#[derive(Clone)]
@ -1057,9 +1054,12 @@ impl TestStruct {
fn get_field(&mut self, index: i64) -> i64 {
self.fields[index as usize]
}
fn set_field(&mut self, index: i64, value: i64) {
self.fields[index as usize] = value
}
fn new() -> Self {
TestStruct { fields: vec![1, 2, 42, 4, 5] }
TestStruct { fields: vec![1, 2, 3, 4, 5] }
}
}
@ -1068,22 +1068,31 @@ let engine = Engine::new();
engine.register_type::<TestStruct>();
engine.register_fn("new_ts", TestStruct::new);
engine.register_indexer(TestStruct::get_field);
let result = engine.eval::<i64>("let a = new_ts(); a[2]")?;
// Shorthand: engine.register_indexer_get_set(TestStruct::get_field, TestStruct::set_field);
engine.register_indexer_get(TestStruct::get_field);
engine.register_indexer_set(TestStruct::set_field);
let result = engine.eval::<i64>("let a = new_ts(); a[2] = 42; a[2]")?;
println!("Answer: {}", result); // prints 42
```
Needless to say, `register_type`, `register_type_with_name`, `register_get`, `register_set`, `register_get_set`
and `register_indexer` are not available under the [`no_object`] feature.
`register_indexer` is also not available under the [`no_index`] feature.
For efficiency reasons, indexers **cannot** be used to overload (i.e. override) built-in indexing operations for
[arrays] and [object maps].
Printing for custom types
-------------------------
### Disabling custom types
To use custom types for `print` and `debug`, or format its value into a [string], it is necessary that the following
functions be registered (assuming the custom type is `T` and it is `Display + Debug`):
The custom types API `register_type`, `register_type_with_name`, `register_get`, `register_set`, `register_get_set`,
`register_indexer_get`, `register_indexer_set` and `register_indexer_get_set` are not available under [`no_object`].
The indexers API `register_indexer_get`, `register_indexer_set` and `register_indexer_get_set` are also
not available under [`no_index`].
### Printing for custom types
To use custom types for `print` and `debug`, or convert its value into a [string], it is necessary that the following
functions be registered (assuming the custom type is `T : Display + Debug`):
| Function | Signature | Typical implementation | Usage |
| ----------- | ------------------------------------------------ | ------------------------------ | --------------------------------------------------------------------------------------- |
@ -1103,7 +1112,7 @@ By default, Rhai treats each [`Engine`] invocation as a fresh one, persisting on
but no global state. This gives each evaluation a clean starting slate. In order to continue using the same global state
from one invocation to the next, such a state must be manually created and passed in.
All `Scope` variables are [`Dynamic`], meaning they can store values of any type. Under the [`sync`] feature, however,
All `Scope` variables are [`Dynamic`], meaning they can store values of any type. Under [`sync`], however,
only types that are `Send + Sync` are supported, and the entire `Scope` itself will also be `Send + Sync`.
This is extremely useful in multi-threaded applications.
@ -1205,7 +1214,7 @@ The following are reserved keywords in Rhai:
| `import`, `export`, `as` | Modules | [`no_module`] |
Keywords cannot be the name of a [function] or [variable], unless the relevant exclusive feature is enabled.
For example, `fn` is a valid variable name under the [`no_function`] feature.
For example, `fn` is a valid variable name under [`no_function`].
Statements
----------
@ -2375,10 +2384,10 @@ which simply loads a script file based on the path (with `.rhai` extension attac
Built-in module resolvers are grouped under the `rhai::module_resolvers` module namespace.
| Module Resolver | Description |
| ---------------------- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| `FileModuleResolver` | The default module resolution service, not available under the [`no_std`] feature. Loads a script file (based off the current directory) with `.rhai` extension.<br/>The base directory can be changed via the `FileModuleResolver::new_with_path()` constructor function.<br/>`FileModuleResolver::create_module()` loads a script file and returns a module. |
| `StaticModuleResolver` | Loads modules that are statically added. This can be used under the [`no_std`] feature. |
| Module Resolver | Description |
| ---------------------- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| `FileModuleResolver` | The default module resolution service, not available under [`no_std`]. Loads a script file (based off the current directory) with `.rhai` extension.<br/>The base directory can be changed via the `FileModuleResolver::new_with_path()` constructor function.<br/>`FileModuleResolver::create_module()` loads a script file and returns a module. |
| `StaticModuleResolver` | Loads modules that are statically added. This can be used under [`no_std`]. |
An [`Engine`]'s module resolver is set via a call to `Engine::set_module_resolver`:

7
RELEASES.md
View File

@ -8,6 +8,13 @@ Breaking changes
----------------
* Callback closure passed to `Engine::on_progress` now takes `&u64` instead of `u64` to be consistent with other callback signatures.
* `Engine::register_indexer` is renamed to `Engine::register_indexer_get`.
* `Module::set_indexer_fn` is renamed to `Module::set_indexer_get_fn`.
New features
------------
* Indexers are now split into getters ans setters (which now support updates). The API is split into `Engine::register_indexer_get` and `Engine::register_indexer_set` with `Engine::register_indexer_get_set` being a shorthand. Similarly, `Module::set_indexer_get_fn` and `Module::set_indexer_set_fn` are added.
Version 0.15.0

107
src/api.rs
View File

@ -2,7 +2,8 @@
use crate::any::{Dynamic, Variant};
use crate::engine::{
get_script_function_by_signature, make_getter, make_setter, Engine, State, FUNC_INDEXER,
get_script_function_by_signature, make_getter, make_setter, Engine, State, FUNC_INDEXER_GET,
FUNC_INDEXER_SET,
};
use crate::error::ParseError;
use crate::fn_call::FuncArgs;
@ -275,7 +276,7 @@ impl Engine {
self.register_set(name, set_fn);
}
/// Register an indexer function for a registered type with the `Engine`.
/// Register an index getter for a registered type with the `Engine`.
///
/// The function signature must start with `&mut self` and not `&self`.
///
@ -305,7 +306,7 @@ impl Engine {
/// engine.register_fn("new_ts", TestStruct::new);
///
/// // Register an indexer.
/// engine.register_indexer(TestStruct::get_field);
/// engine.register_indexer_get(TestStruct::get_field);
///
/// assert_eq!(engine.eval::<i64>("let a = new_ts(); a[2]")?, 3);
/// # Ok(())
@ -313,7 +314,7 @@ impl Engine {
/// ```
#[cfg(not(feature = "no_object"))]
#[cfg(not(feature = "no_index"))]
pub fn register_indexer<T, X, U>(
pub fn register_indexer_get<T, X, U>(
&mut self,
callback: impl Fn(&mut T, X) -> U + SendSync + 'static,
) where
@ -321,7 +322,103 @@ impl Engine {
U: Variant + Clone,
X: Variant + Clone,
{
self.register_fn(FUNC_INDEXER, callback);
self.register_fn(FUNC_INDEXER_GET, callback);
}
/// Register an index setter for a registered type with the `Engine`.
///
/// # Example
///
/// ```
/// #[derive(Clone)]
/// struct TestStruct {
/// fields: Vec<i64>
/// }
///
/// impl TestStruct {
/// fn new() -> Self { TestStruct { fields: vec![1, 2, 3, 4, 5] } }
/// fn set_field(&mut self, index: i64, value: i64) { self.fields[index as usize] = value; }
/// }
///
/// # fn main() -> Result<(), Box<rhai::EvalAltResult>> {
/// use rhai::{Engine, RegisterFn};
///
/// let mut engine = Engine::new();
///
/// // Register the custom type.
/// engine.register_type::<TestStruct>();
///
/// engine.register_fn("new_ts", TestStruct::new);
///
/// // Register an indexer.
/// engine.register_indexer_set(TestStruct::set_field);
///
/// assert_eq!(
/// engine.eval::<TestStruct>("let a = new_ts(); a[2] = 42; a")?.fields[2],
/// 42
/// );
/// # Ok(())
/// # }
/// ```
#[cfg(not(feature = "no_object"))]
#[cfg(not(feature = "no_index"))]
pub fn register_indexer_set<T, X, U>(
&mut self,
callback: impl Fn(&mut T, X, U) -> () + SendSync + 'static,
) where
T: Variant + Clone,
U: Variant + Clone,
X: Variant + Clone,
{
self.register_fn(FUNC_INDEXER_SET, callback);
}
/// Shorthand for register both index getter and setter functions for a registered type with the `Engine`.
///
/// # Example
///
/// ```
/// #[derive(Clone)]
/// struct TestStruct {
/// fields: Vec<i64>
/// }
///
/// impl TestStruct {
/// fn new() -> Self { TestStruct { fields: vec![1, 2, 3, 4, 5] } }
/// fn get_field(&mut self, index: i64) -> i64 { self.fields[index as usize] }
/// fn set_field(&mut self, index: i64, value: i64) { self.fields[index as usize] = value; }
/// }
///
/// # fn main() -> Result<(), Box<rhai::EvalAltResult>> {
/// use rhai::{Engine, RegisterFn};
///
/// let mut engine = Engine::new();
///
/// // Register the custom type.
/// engine.register_type::<TestStruct>();
///
/// engine.register_fn("new_ts", TestStruct::new);
///
/// // Register an indexer.
/// engine.register_indexer_get_set(TestStruct::get_field, TestStruct::set_field);
///
/// assert_eq!(engine.eval::<i64>("let a = new_ts(); a[2] = 42; a[2]")?, 42);
/// # Ok(())
/// # }
/// ```
#[cfg(not(feature = "no_object"))]
#[cfg(not(feature = "no_index"))]
pub fn register_indexer_get_set<T, X, U>(
&mut self,
getter: impl Fn(&mut T, X) -> U + SendSync + 'static,
setter: impl Fn(&mut T, X, U) -> () + SendSync + 'static,
) where
T: Variant + Clone,
U: Variant + Clone,
X: Variant + Clone,
{
self.register_indexer_get(getter);
self.register_indexer_set(setter);
}
/// Compile a string into an `AST`, which can be used later for evaluation.

220
src/engine.rs
View File

@ -74,9 +74,11 @@ pub const KEYWORD_EVAL: &str = "eval";
pub const FUNC_TO_STRING: &str = "to_string";
pub const FUNC_GETTER: &str = "get$";
pub const FUNC_SETTER: &str = "set$";
pub const FUNC_INDEXER: &str = "$index$";
pub const FUNC_INDEXER_GET: &str = "$index$get$";
pub const FUNC_INDEXER_SET: &str = "$index$set$";
/// A type that encapsulates a mutation target for an expression with side effects.
#[derive(Debug)]
enum Target<'a> {
/// The target is a mutable reference to a `Dynamic` value somewhere.
Ref(&'a mut Dynamic),
@ -91,40 +93,45 @@ impl Target<'_> {
/// Is the `Target` a reference pointing to other data?
pub fn is_ref(&self) -> bool {
match self {
Target::Ref(_) => true,
Target::Value(_) | Target::StringChar(_, _, _) => false,
Self::Ref(_) => true,
Self::Value(_) | Self::StringChar(_, _, _) => false,
}
}
/// Is the `Target` an owned value?
pub fn is_value(&self) -> bool {
match self {
Self::Ref(_) => false,
Self::Value(_) => true,
Self::StringChar(_, _, _) => false,
}
}
/// Get the value of the `Target` as a `Dynamic`, cloning a referenced value if necessary.
pub fn clone_into_dynamic(self) -> Dynamic {
match self {
Target::Ref(r) => r.clone(), // Referenced value is cloned
Target::Value(v) => v, // Owned value is simply taken
Target::StringChar(_, _, ch) => ch, // Character is taken
Self::Ref(r) => r.clone(), // Referenced value is cloned
Self::Value(v) => v, // Owned value is simply taken
Self::StringChar(_, _, ch) => ch, // Character is taken
}
}
/// Get a mutable reference from the `Target`.
pub fn as_mut(&mut self) -> &mut Dynamic {
match self {
Target::Ref(r) => *r,
Target::Value(ref mut r) => r,
Target::StringChar(_, _, ref mut r) => r,
Self::Ref(r) => *r,
Self::Value(ref mut r) => r,
Self::StringChar(_, _, ref mut r) => r,
}
}
/// Update the value of the `Target`.
/// Position in `EvalAltResult` is None and must be set afterwards.
pub fn set_value(&mut self, new_val: Dynamic) -> Result<(), Box<EvalAltResult>> {
match self {
Target::Ref(r) => **r = new_val,
Target::Value(_) => {
Self::Ref(r) => **r = new_val,
Self::Value(_) => {
return Err(Box::new(EvalAltResult::ErrorAssignmentToUnknownLHS(
Position::none(),
)))
}
Target::StringChar(Dynamic(Union::Str(ref mut s)), index, _) => {
Self::StringChar(Dynamic(Union::Str(ref mut s)), index, _) => {
// Replace the character at the specified index position
let new_ch = new_val
.as_char()
@ -163,20 +170,17 @@ impl<T: Into<Dynamic>> From<T> for Target<'_> {
///
/// This type uses some unsafe code, mainly for avoiding cloning of local variable names via
/// direct lifetime casting.
#[derive(Debug, Clone, Default)]
#[derive(Debug, Eq, PartialEq, Hash, Clone, Default)]
pub struct State {
/// Normally, access to variables are parsed with a relative offset into the scope to avoid a lookup.
/// In some situation, e.g. after running an `eval` statement, subsequent offsets become mis-aligned.
/// When that happens, this flag is turned on to force a scope lookup by name.
pub always_search: bool,
/// Level of the current scope. The global (root) level is zero, a new block (or function call)
/// is one level higher, and so on.
pub scope_level: usize,
/// Number of operations performed.
pub operations: u64,
/// Number of modules loaded.
pub modules: u64,
}
@ -361,14 +365,23 @@ fn search_scope<'s, 'a>(
_ => unreachable!(),
};
// Check if it is qualified
if let Some(modules) = modules.as_ref() {
let module = if let Some(index) = modules.index() {
// Qualified - check if the root module is directly indexed
let index = if state.always_search {
None
} else {
modules.index()
};
let module = if let Some(index) = index {
scope
.get_mut(scope.len() - index.get())
.0
.downcast_mut::<Module>()
.unwrap()
} else {
// Find the root module in the scope
let (id, root_pos) = modules.get(0);
scope
@ -376,28 +389,27 @@ fn search_scope<'s, 'a>(
.ok_or_else(|| Box::new(EvalAltResult::ErrorModuleNotFound(id.into(), *root_pos)))?
};
return Ok((
module.get_qualified_var_mut(name, *hash_var, *pos)?,
name,
// Module variables are constant
ScopeEntryType::Constant,
*pos,
));
}
let target = module.get_qualified_var_mut(name, *hash_var, *pos)?;
let index = if state.always_search { None } else { *index };
let index = if let Some(index) = index {
scope.len() - index.get()
// Module variables are constant
Ok((target, name, ScopeEntryType::Constant, *pos))
} else {
scope
.get_index(name)
.ok_or_else(|| Box::new(EvalAltResult::ErrorVariableNotFound(name.into(), *pos)))?
.0
};
// Unqualified - check if it is directly indexed
let index = if state.always_search { None } else { *index };
let (val, typ) = scope.get_mut(index);
Ok((val, name, typ, *pos))
let index = if let Some(index) = index {
scope.len() - index.get()
} else {
// Find the variable in the scope
scope
.get_index(name)
.ok_or_else(|| Box::new(EvalAltResult::ErrorVariableNotFound(name.into(), *pos)))?
.0
};
let (val, typ) = scope.get_mut(index);
Ok((val, name, typ, *pos))
}
}
impl Engine {
@ -585,10 +597,16 @@ impl Engine {
.or_else(|| self.packages.get_fn(hashes.0));
if let Some(func) = func {
// Calling pure function in method-call?
normalize_first_arg(
(func.is_pure() || func.is_script()) && is_ref,
&mut this_copy,
&mut old_this_ptr,
args,
);
if func.is_script() {
// Run scripted function
normalize_first_arg(is_ref, &mut this_copy, &mut old_this_ptr, args);
let fn_def = func.get_fn_def();
let result =
self.call_script_fn(scope, state, lib, fn_name, fn_def, args, level)?;
@ -598,14 +616,6 @@ impl Engine {
return Ok((result, false));
} else {
// Calling pure function in method-call?
normalize_first_arg(
func.is_pure() && is_ref,
&mut this_copy,
&mut old_this_ptr,
args,
);
// Run external function
let result = func.get_native_fn()(args)?;
@ -668,22 +678,40 @@ impl Engine {
)));
}
let types_list: Vec<_> = args
.iter()
.map(|name| self.map_type_name(name.type_name()))
.collect();
// Getter function not found?
if fn_name == FUNC_INDEXER {
// index getter function not found?
if fn_name == FUNC_INDEXER_GET && args.len() == 2 {
return Err(Box::new(EvalAltResult::ErrorFunctionNotFound(
format!("[]({})", types_list.join(", ")),
format!(
"{} [{}]",
self.map_type_name(args[0].type_name()),
self.map_type_name(args[1].type_name()),
),
Position::none(),
)));
}
// index setter function not found?
if fn_name == FUNC_INDEXER_SET {
return Err(Box::new(EvalAltResult::ErrorFunctionNotFound(
format!(
"{} [{}]=",
self.map_type_name(args[0].type_name()),
self.map_type_name(args[1].type_name()),
),
Position::none(),
)));
}
// Raise error
Err(Box::new(EvalAltResult::ErrorFunctionNotFound(
format!("{} ({})", fn_name, types_list.join(", ")),
format!(
"{} ({})",
fn_name,
args.iter()
.map(|name| self.map_type_name(name.type_name()))
.collect::<Vec<_>>()
.join(", ")
),
Position::none(),
)))
}
@ -787,12 +815,8 @@ impl Engine {
level: usize,
) -> Result<(Dynamic, bool), Box<EvalAltResult>> {
// Qualifiers (none) + function name + number of arguments + argument `TypeId`'s.
let hash_fn = calc_fn_hash(
empty(),
fn_name,
args.len(),
args.iter().map(|a| a.type_id()),
);
let arg_types = args.iter().map(|a| a.type_id());
let hash_fn = calc_fn_hash(empty(), fn_name, args.len(), arg_types);
let hashes = (hash_fn, if native_only { 0 } else { hash_fn_def });
match fn_name {
@ -890,8 +914,8 @@ impl Engine {
let (idx, expr, pos) = x.as_ref();
let is_idx = matches!(rhs, Expr::Index(_));
let idx_pos = idx.position();
let this_ptr = &mut self
.get_indexed_mut(state, lib, obj, is_ref, idx_val, idx_pos, false)?;
let this_ptr =
&mut self.get_indexed_mut(state, lib, target, idx_val, idx_pos, false)?;
self.eval_dot_index_chain_helper(
state, lib, this_ptr, expr, idx_values, is_idx, level, new_val,
@ -900,17 +924,52 @@ impl Engine {
}
// xxx[rhs] = new_val
_ if new_val.is_some() => {
let this_ptr =
&mut self.get_indexed_mut(state, lib, obj, is_ref, idx_val, pos, true)?;
let mut idx_val2 = idx_val.clone();
this_ptr
.set_value(new_val.unwrap())
.map_err(|err| EvalAltResult::new_position(err, rhs.position()))?;
Ok((Default::default(), true))
match self.get_indexed_mut(state, lib, target, idx_val, pos, true) {
// Indexed value is an owned value - the only possibility is an indexer
// Try to call an index setter
Ok(this_ptr) if this_ptr.is_value() => {
let fn_name = FUNC_INDEXER_SET;
let args = &mut [target.as_mut(), &mut idx_val2, &mut new_val.unwrap()];
self.exec_fn_call(state, lib, fn_name, true, 0, args, is_ref, None, 0)
.or_else(|err| match *err {
// If there is no index setter, no need to set it back because the indexer is read-only
EvalAltResult::ErrorFunctionNotFound(s, _)
if s == FUNC_INDEXER_SET =>
{
Ok(Default::default())
}
_ => Err(err),
})?;
}
// Indexed value is a reference - update directly
Ok(ref mut this_ptr) => {
this_ptr
.set_value(new_val.unwrap())
.map_err(|err| EvalAltResult::new_position(err, rhs.position()))?;
}
Err(err) => match *err {
// No index getter - try to call an index setter
EvalAltResult::ErrorIndexingType(_, _) => {
let fn_name = FUNC_INDEXER_SET;
let args =
&mut [target.as_mut(), &mut idx_val2, &mut new_val.unwrap()];
self.exec_fn_call(
state, lib, fn_name, true, 0, args, is_ref, None, 0,
)?;
}
// Error
err => return Err(Box::new(err)),
},
}
Ok(Default::default())
}
// xxx[rhs]
_ => self
.get_indexed_mut(state, lib, obj, is_ref, idx_val, pos, false)
.get_indexed_mut(state, lib, target, idx_val, pos, false)
.map(|v| (v.clone_into_dynamic(), false)),
}
} else {
@ -940,8 +999,7 @@ impl Engine {
Expr::Property(x) if obj.is::<Map>() && new_val.is_some() => {
let ((prop, _, _), pos) = x.as_ref();
let index = prop.clone().into();
let mut val =
self.get_indexed_mut(state, lib, obj, is_ref, index, *pos, true)?;
let mut val = self.get_indexed_mut(state, lib, target, index, *pos, true)?;
val.set_value(new_val.unwrap())
.map_err(|err| EvalAltResult::new_position(err, rhs.position()))?;
@ -952,7 +1010,7 @@ impl Engine {
Expr::Property(x) if obj.is::<Map>() => {
let ((prop, _, _), pos) = x.as_ref();
let index = prop.clone().into();
let val = self.get_indexed_mut(state, lib, obj, is_ref, index, *pos, false)?;
let val = self.get_indexed_mut(state, lib, target, index, *pos, false)?;
Ok((val.clone_into_dynamic(), false))
}
@ -981,7 +1039,7 @@ impl Engine {
let mut val = if let Expr::Property(p) = prop {
let ((prop, _, _), _) = p.as_ref();
let index = prop.clone().into();
self.get_indexed_mut(state, lib, obj, is_ref, index, *pos, false)?
self.get_indexed_mut(state, lib, target, index, *pos, false)?
} else {
unreachable!();
};
@ -1160,14 +1218,16 @@ impl Engine {
&self,
state: &mut State,
lib: &Module,
val: &'a mut Dynamic,
is_ref: bool,
target: &'a mut Target,
mut idx: Dynamic,
idx_pos: Position,
create: bool,
) -> Result<Target<'a>, Box<EvalAltResult>> {
self.inc_operations(state)?;
let is_ref = target.is_ref();
let val = target.as_mut();
match val {
#[cfg(not(feature = "no_index"))]
Dynamic(Union::Array(arr)) => {
@ -1233,7 +1293,7 @@ impl Engine {
}
_ => {
let fn_name = FUNC_INDEXER;
let fn_name = FUNC_INDEXER_GET;
let type_name = self.map_type_name(val.type_name());
let args = &mut [val, &mut idx];
self.exec_fn_call(state, lib, fn_name, true, 0, args, is_ref, None, 0)

48
src/module.rs
View File

@ -2,7 +2,7 @@
use crate::any::{Dynamic, Variant};
use crate::calc_fn_hash;
use crate::engine::{make_getter, make_setter, Engine, FUNC_INDEXER};
use crate::engine::{make_getter, make_setter, Engine, FUNC_INDEXER_GET, FUNC_INDEXER_SET};
use crate::fn_native::{CallableFunction, FnCallArgs, IteratorFn, SendSync};
use crate::parser::{
FnAccess,
@ -518,7 +518,7 @@ impl Module {
self.set_fn_2_mut(make_setter(&name.into()), func)
}
/// Set a Rust indexer function taking two parameters (the first one mutable) into the module,
/// Set a Rust index getter taking two parameters (the first one mutable) into the module,
/// returning a hash key.
///
/// If there is a similar existing setter Rust function, it is replaced.
@ -529,19 +529,19 @@ impl Module {
/// use rhai::{Module, ImmutableString};
///
/// let mut module = Module::new();
/// let hash = module.set_indexer_fn(|x: &mut i64, y: ImmutableString| {
/// let hash = module.set_indexer_get_fn(|x: &mut i64, y: ImmutableString| {
/// Ok(*x + y.len() as i64)
/// });
/// assert!(module.get_fn(hash).is_some());
/// ```
#[cfg(not(feature = "no_object"))]
#[cfg(not(feature = "no_index"))]
pub fn set_indexer_fn<A: Variant + Clone, B: Variant + Clone, T: Variant + Clone>(
pub fn set_indexer_get_fn<A: Variant + Clone, B: Variant + Clone, T: Variant + Clone>(
&mut self,
#[cfg(not(feature = "sync"))] func: impl Fn(&mut A, B) -> FuncReturn<T> + 'static,
#[cfg(feature = "sync")] func: impl Fn(&mut A, B) -> FuncReturn<T> + Send + Sync + 'static,
) -> u64 {
self.set_fn_2_mut(FUNC_INDEXER, func)
self.set_fn_2_mut(FUNC_INDEXER_GET, func)
}
/// Set a Rust function taking three parameters into the module, returning a hash key.
@ -629,6 +629,44 @@ impl Module {
)
}
/// Set a Rust index setter taking three parameters (the first one mutable) into the module,
/// returning a hash key.
///
/// If there is a similar existing Rust function, it is replaced.
///
/// # Examples
///
/// ```
/// use rhai::{Module, ImmutableString};
///
/// let mut module = Module::new();
/// let hash = module.set_indexer_set_fn(|x: &mut i64, y: ImmutableString, value: i64| {
/// *x = y.len() as i64 + value;
/// Ok(())
/// });
/// assert!(module.get_fn(hash).is_some());
/// ```
pub fn set_indexer_set_fn<A: Variant + Clone, B: Variant + Clone>(
&mut self,
#[cfg(not(feature = "sync"))] func: impl Fn(&mut A, B, A) -> FuncReturn<()> + 'static,
#[cfg(feature = "sync")] func: impl Fn(&mut A, B, A) -> FuncReturn<()> + Send + Sync + 'static,
) -> u64 {
let f = move |args: &mut FnCallArgs| {
let b = mem::take(args[1]).cast::<B>();
let c = mem::take(args[2]).cast::<A>();
let a = args[0].downcast_mut::<A>().unwrap();
func(a, b, c).map(Dynamic::from)
};
let args = [TypeId::of::<A>(), TypeId::of::<B>(), TypeId::of::<A>()];
self.set_fn(
FUNC_INDEXER_SET,
Public,
&args,
CallableFunction::from_method(Box::new(f)),
)
}
/// Set a Rust function taking four parameters into the module, returning a hash key.
///
/// If there is a similar existing Rust function, it is replaced.

19
tests/get_set.rs
View File

@ -42,18 +42,25 @@ fn test_get_set() -> Result<(), Box<EvalAltResult>> {
engine.register_fn("add", |value: &mut INT| *value += 41);
engine.register_fn("new_ts", TestStruct::new);
#[cfg(not(feature = "no_index"))]
engine.register_indexer(|value: &mut TestStruct, index: ImmutableString| {
value.array[index.len()]
});
assert_eq!(engine.eval::<INT>("let a = new_ts(); a.x = 500; a.x")?, 500);
assert_eq!(engine.eval::<INT>("let a = new_ts(); a.x.add(); a.x")?, 42);
assert_eq!(engine.eval::<INT>("let a = new_ts(); a.y.add(); a.y")?, 0);
#[cfg(not(feature = "no_index"))]
assert_eq!(engine.eval::<INT>(r#"let a = new_ts(); a["abc"]"#)?, 4);
{
engine.register_indexer_get_set(
|value: &mut TestStruct, index: ImmutableString| value.array[index.len()],
|value: &mut TestStruct, index: ImmutableString, new_val: INT| {
value.array[index.len()] = new_val
},
);
assert_eq!(engine.eval::<INT>(r#"let a = new_ts(); a["abc"]"#)?, 4);
assert_eq!(
engine.eval::<INT>(r#"let a = new_ts(); a["abc"] = 42; a["abc"]"#)?,
42
);
}
Ok(())
}