495 lines
17 KiB
Rust
495 lines
17 KiB
Rust
//! # Rhai - embedded scripting for Rust
|
|
//!
|
|
//! 
|
|
//!
|
|
//! Rhai is a tiny, simple and fast embedded scripting language for Rust
|
|
//! that gives you a safe and easy way to add scripting to your applications.
|
|
//!
|
|
//! It provides a familiar syntax based on JavaScript+Rust and a simple Rust interface.
|
|
//!
|
|
//! # A Quick Example
|
|
//!
|
|
//! ## Contents of `my_script.rhai`
|
|
//!
|
|
//! ```rhai
|
|
//! /// Brute force factorial function
|
|
//! fn factorial(x) {
|
|
//! if x == 1 { return 1; }
|
|
//! x * factorial(x - 1)
|
|
//! }
|
|
//!
|
|
//! // Calling an external function 'compute'
|
|
//! compute(factorial(10))
|
|
//! ```
|
|
//!
|
|
//! ## The Rust part
|
|
//!
|
|
//! ```no_run
|
|
//! use rhai::{Engine, EvalAltResult};
|
|
//!
|
|
//! fn main() -> Result<(), Box<EvalAltResult>>
|
|
//! {
|
|
//! // Define external function
|
|
//! fn compute_something(x: i64) -> bool {
|
|
//! (x % 40) == 0
|
|
//! }
|
|
//!
|
|
//! // Create scripting engine
|
|
//! let mut engine = Engine::new();
|
|
//!
|
|
//! // Register external function as 'compute'
|
|
//! engine.register_fn("compute", compute_something);
|
|
//!
|
|
//! # #[cfg(not(feature = "no_std"))]
|
|
//! # #[cfg(not(target_family = "wasm"))]
|
|
//! #
|
|
//! // Evaluate the script, expecting a 'bool' result
|
|
//! let result: bool = engine.eval_file("my_script.rhai".into())?;
|
|
//!
|
|
//! assert_eq!(result, true);
|
|
//!
|
|
//! Ok(())
|
|
//! }
|
|
//! ```
|
|
//!
|
|
//! # Features
|
|
//!
|
|
#![cfg_attr(feature = "document-features", doc = document_features::document_features!(feature_label = "<span id=\"feature-{feature}\">**`{feature}`**</span>"))]
|
|
//!
|
|
//! # On-Line Documentation
|
|
//!
|
|
//! See [The Rhai Book](https://rhai.rs/book) for details on the Rhai scripting engine and language.
|
|
|
|
#![cfg_attr(feature = "no_std", no_std)]
|
|
#![deny(missing_docs)]
|
|
// #![warn(clippy::all)]
|
|
// #![warn(clippy::pedantic)]
|
|
// #![warn(clippy::nursery)]
|
|
#![warn(clippy::cargo)]
|
|
// #![warn(clippy::undocumented_unsafe_blocks)]
|
|
#![allow(clippy::unit_arg)]
|
|
#![allow(clippy::missing_errors_doc)]
|
|
#![allow(clippy::missing_panics_doc)]
|
|
#![allow(clippy::used_underscore_binding)]
|
|
#![allow(clippy::inline_always)]
|
|
#![allow(clippy::module_name_repetitions)]
|
|
#![allow(clippy::negative_feature_names)]
|
|
#![allow(clippy::module_inception)]
|
|
#![allow(clippy::box_collection)]
|
|
#![allow(clippy::too_many_arguments)]
|
|
#![allow(clippy::upper_case_acronyms)]
|
|
#![allow(clippy::match_same_arms)]
|
|
// The lints below can be turned off to reduce signal/noise ratio
|
|
// #![allow(clippy::too_many_lines)]
|
|
// #![allow(clippy::let_underscore_drop)]
|
|
// #![allow(clippy::absurd_extreme_comparisons)]
|
|
// #![allow(clippy::unnecessary_cast)]
|
|
// #![allow(clippy::wildcard_imports)]
|
|
|
|
#[cfg(feature = "no_std")]
|
|
extern crate alloc;
|
|
|
|
#[cfg(feature = "no_std")]
|
|
extern crate no_std_compat as std;
|
|
|
|
#[cfg(feature = "no_std")]
|
|
use std::prelude::v1::*;
|
|
|
|
// Internal modules
|
|
#[macro_use]
|
|
mod reify;
|
|
#[macro_use]
|
|
mod restore;
|
|
|
|
mod api;
|
|
mod ast;
|
|
pub mod config;
|
|
mod engine;
|
|
mod eval;
|
|
mod func;
|
|
mod module;
|
|
mod optimizer;
|
|
pub mod packages;
|
|
mod parser;
|
|
#[cfg(feature = "serde")]
|
|
pub mod serde;
|
|
mod tests;
|
|
mod tokenizer;
|
|
mod types;
|
|
|
|
/// Error encountered when parsing a script.
|
|
type PERR = ParseErrorType;
|
|
/// Evaluation result.
|
|
type ERR = EvalAltResult;
|
|
/// General evaluation error for Rhai scripts.
|
|
type RhaiError = Box<ERR>;
|
|
/// Generic [`Result`] type for Rhai functions.
|
|
type RhaiResultOf<T> = Result<T, RhaiError>;
|
|
/// General [`Result`] type for Rhai functions returning [`Dynamic`] values.
|
|
type RhaiResult = RhaiResultOf<Dynamic>;
|
|
|
|
/// The system integer type. It is defined as [`i64`].
|
|
///
|
|
/// If the `only_i32` feature is enabled, this will be [`i32`] instead.
|
|
#[cfg(not(feature = "only_i32"))]
|
|
pub type INT = i64;
|
|
|
|
/// The system integer type.
|
|
/// It is defined as [`i32`] since the `only_i32` feature is used.
|
|
///
|
|
/// If the `only_i32` feature is not used, this will be `i64` instead.
|
|
#[cfg(feature = "only_i32")]
|
|
pub type INT = i32;
|
|
|
|
/// The unsigned system base integer type. It is defined as [`u64`].
|
|
///
|
|
/// If the `only_i32` feature is enabled, this will be [`u32`] instead.
|
|
#[cfg(not(feature = "only_i32"))]
|
|
#[allow(non_camel_case_types)]
|
|
type UNSIGNED_INT = u64;
|
|
|
|
/// The unsigned system integer base type.
|
|
/// It is defined as [`u32`] since the `only_i32` feature is used.
|
|
///
|
|
/// If the `only_i32` feature is not used, this will be `u64` instead.
|
|
#[cfg(feature = "only_i32")]
|
|
#[allow(non_camel_case_types)]
|
|
type UNSIGNED_INT = u32;
|
|
|
|
/// The maximum integer that can fit into a [`usize`].
|
|
#[cfg(not(target_pointer_width = "32"))]
|
|
const MAX_USIZE_INT: INT = INT::MAX;
|
|
|
|
/// The maximum integer that can fit into a [`usize`].
|
|
#[cfg(not(feature = "only_i32"))]
|
|
#[cfg(target_pointer_width = "32")]
|
|
const MAX_USIZE_INT: INT = usize::MAX as INT;
|
|
|
|
/// The maximum integer that can fit into a [`usize`].
|
|
#[cfg(feature = "only_i32")]
|
|
#[cfg(target_pointer_width = "32")]
|
|
const MAX_USIZE_INT: INT = INT::MAX;
|
|
|
|
/// Number of bits in [`INT`].
|
|
///
|
|
/// It is 64 unless the `only_i32` feature is enabled when it will be 32.
|
|
const INT_BITS: usize = std::mem::size_of::<INT>() * 8;
|
|
|
|
/// Number of bytes that make up an [`INT`].
|
|
///
|
|
/// It is 8 unless the `only_i32` feature is enabled when it will be 4.
|
|
#[cfg(not(feature = "no_index"))]
|
|
const INT_BYTES: usize = std::mem::size_of::<INT>();
|
|
|
|
/// The system floating-point type. It is defined as [`f64`].
|
|
///
|
|
/// Not available under `no_float`.
|
|
///
|
|
/// If the `f32_float` feature is enabled, this will be [`f32`] instead.
|
|
#[cfg(not(feature = "no_float"))]
|
|
#[cfg(not(feature = "f32_float"))]
|
|
pub type FLOAT = f64;
|
|
|
|
/// The system floating-point type.
|
|
/// It is defined as [`f32`] since the `f32_float` feature is used.
|
|
///
|
|
/// Not available under `no_float`.
|
|
///
|
|
/// If the `f32_float` feature is not used, this will be `f64` instead.
|
|
#[cfg(not(feature = "no_float"))]
|
|
#[cfg(feature = "f32_float")]
|
|
pub type FLOAT = f32;
|
|
|
|
/// Number of bytes that make up a [`FLOAT`].
|
|
///
|
|
/// It is 8 unless the `f32_float` feature is enabled when it will be 4.
|
|
#[cfg(not(feature = "no_float"))]
|
|
#[cfg(not(feature = "no_index"))]
|
|
const FLOAT_BYTES: usize = std::mem::size_of::<FLOAT>();
|
|
|
|
/// An exclusive integer range.
|
|
type ExclusiveRange = std::ops::Range<INT>;
|
|
|
|
/// An inclusive integer range.
|
|
type InclusiveRange = std::ops::RangeInclusive<INT>;
|
|
|
|
#[allow(deprecated)]
|
|
pub use api::build_type::{CustomType, TypeBuilder};
|
|
#[cfg(not(feature = "no_custom_syntax"))]
|
|
pub use api::custom_syntax::Expression;
|
|
#[cfg(not(feature = "no_std"))]
|
|
#[cfg(not(target_family = "wasm"))]
|
|
pub use api::files::{eval_file, run_file};
|
|
pub use api::{eval::eval, events::VarDefInfo, run::run};
|
|
pub use ast::{FnAccess, AST};
|
|
pub use engine::{Engine, OP_CONTAINS, OP_EQUALS};
|
|
pub use eval::EvalContext;
|
|
use func::{calc_fn_hash, calc_fn_hash_full, calc_var_hash};
|
|
pub use func::{plugin, FuncArgs, NativeCallContext, RegisterNativeFunction};
|
|
pub use module::{FnNamespace, Module};
|
|
use restore::RestoreOnDrop;
|
|
pub use rhai_codegen::*;
|
|
#[cfg(not(feature = "no_time"))]
|
|
pub use types::Instant;
|
|
pub use types::{
|
|
Dynamic, EvalAltResult, FnPtr, ImmutableString, LexError, ParseError, ParseErrorType, Position,
|
|
Scope,
|
|
};
|
|
|
|
/// _(debugging)_ Module containing types for debugging.
|
|
/// Exported under the `debugging` feature only.
|
|
#[cfg(feature = "debugging")]
|
|
pub mod debugger {
|
|
#[cfg(not(feature = "no_function"))]
|
|
pub use super::eval::CallStackFrame;
|
|
pub use super::eval::{BreakPoint, Debugger, DebuggerCommand, DebuggerEvent};
|
|
}
|
|
|
|
/// An identifier in Rhai. [`SmartString`](https://crates.io/crates/smartstring) is used because most
|
|
/// identifiers are ASCII and short, fewer than 23 characters, so they can be stored inline.
|
|
#[cfg(not(feature = "internals"))]
|
|
type Identifier = SmartString;
|
|
|
|
/// An identifier in Rhai. [`SmartString`](https://crates.io/crates/smartstring) is used because most
|
|
/// identifiers are ASCII and short, fewer than 23 characters, so they can be stored inline.
|
|
#[cfg(feature = "internals")]
|
|
pub type Identifier = SmartString;
|
|
|
|
/// Alias to [`Rc`][std::rc::Rc] or [`Arc`][std::sync::Arc] depending on the `sync` feature flag.
|
|
pub use func::Shared;
|
|
|
|
/// Alias to [`RefCell`][std::cell::RefCell] or [`RwLock`][std::sync::RwLock] depending on the `sync` feature flag.
|
|
pub use func::Locked;
|
|
|
|
/// A shared [`Module`].
|
|
type SharedModule = Shared<Module>;
|
|
|
|
#[cfg(not(feature = "no_function"))]
|
|
pub use func::Func;
|
|
|
|
#[cfg(not(feature = "no_function"))]
|
|
pub use ast::ScriptFnMetadata;
|
|
|
|
#[cfg(not(feature = "no_function"))]
|
|
pub use api::call_fn::CallFnOptions;
|
|
|
|
/// Variable-sized array of [`Dynamic`] values.
|
|
///
|
|
/// Not available under `no_index`.
|
|
#[cfg(not(feature = "no_index"))]
|
|
pub type Array = Vec<Dynamic>;
|
|
|
|
/// Variable-sized array of [`u8`] values (byte array).
|
|
///
|
|
/// Not available under `no_index`.
|
|
#[cfg(not(feature = "no_index"))]
|
|
pub type Blob = Vec<u8>;
|
|
|
|
/// A dictionary of [`Dynamic`] values with string keys.
|
|
///
|
|
/// Not available under `no_object`.
|
|
///
|
|
/// [`SmartString`](https://crates.io/crates/smartstring) is used as the key type because most
|
|
/// property names are ASCII and short, fewer than 23 characters, so they can be stored inline.
|
|
#[cfg(not(feature = "no_object"))]
|
|
pub type Map = std::collections::BTreeMap<Identifier, Dynamic>;
|
|
|
|
#[cfg(not(feature = "no_object"))]
|
|
pub use api::json::format_map_as_json;
|
|
|
|
#[cfg(not(feature = "no_module"))]
|
|
pub use module::ModuleResolver;
|
|
|
|
/// Module containing all built-in _module resolvers_ available to Rhai.
|
|
#[cfg(not(feature = "no_module"))]
|
|
pub use module::resolvers as module_resolvers;
|
|
|
|
#[cfg(not(feature = "no_optimize"))]
|
|
pub use optimizer::OptimizationLevel;
|
|
|
|
/// Placeholder for the optimization level.
|
|
#[cfg(feature = "no_optimize")]
|
|
pub type OptimizationLevel = ();
|
|
|
|
// Expose internal data structures.
|
|
|
|
#[cfg(feature = "internals")]
|
|
pub use types::dynamic::{AccessMode, DynamicReadLock, DynamicWriteLock, Variant};
|
|
|
|
#[cfg(feature = "internals")]
|
|
#[cfg(not(feature = "no_float"))]
|
|
pub use types::FloatWrapper;
|
|
|
|
#[cfg(feature = "internals")]
|
|
pub use types::{Span, StringsInterner};
|
|
|
|
#[cfg(feature = "internals")]
|
|
pub use tokenizer::{
|
|
get_next_token, is_valid_function_name, is_valid_identifier, parse_string_literal, InputStream,
|
|
MultiInputsStream, Token, TokenIterator, TokenizeState, TokenizerControl,
|
|
TokenizerControlBlock,
|
|
};
|
|
|
|
#[cfg(feature = "internals")]
|
|
pub use parser::ParseState;
|
|
|
|
#[cfg(feature = "internals")]
|
|
pub use ast::{
|
|
ASTFlags, ASTNode, BinaryExpr, ConditionalExpr, Expr, FlowControl, FnCallExpr, FnCallHashes,
|
|
Ident, OpAssignment, RangeCase, ScriptFnDef, Stmt, StmtBlock, SwitchCasesCollection,
|
|
};
|
|
|
|
#[cfg(feature = "internals")]
|
|
#[cfg(not(feature = "no_custom_syntax"))]
|
|
pub use ast::CustomExpr;
|
|
|
|
#[cfg(feature = "internals")]
|
|
#[cfg(not(feature = "no_module"))]
|
|
pub use ast::Namespace;
|
|
|
|
#[cfg(feature = "internals")]
|
|
pub use func::EncapsulatedEnviron;
|
|
|
|
#[cfg(feature = "internals")]
|
|
pub use eval::{Caches, FnResolutionCache, FnResolutionCacheEntry, GlobalRuntimeState};
|
|
|
|
#[cfg(feature = "internals")]
|
|
#[allow(deprecated)]
|
|
pub use func::{locked_read, locked_write, CallableFunction, NativeCallContextStore};
|
|
|
|
#[cfg(feature = "internals")]
|
|
#[cfg(feature = "metadata")]
|
|
pub use api::definitions::Definitions;
|
|
|
|
/// Number of items to keep inline for [`StaticVec`].
|
|
const STATIC_VEC_INLINE_SIZE: usize = 3;
|
|
|
|
/// Alias to [`smallvec::SmallVec<[T; 3]>`](https://crates.io/crates/smallvec), which is a
|
|
/// specialized [`Vec`] backed by a small, inline, fixed-size array when there are ≤ 3 items stored.
|
|
///
|
|
/// # History
|
|
///
|
|
/// And Saint Attila raised the `SmallVec` up on high, saying, "O Lord, bless this Thy `SmallVec`
|
|
/// that, with it, Thou mayest blow Thine allocation costs to tiny bits in Thy mercy."
|
|
///
|
|
/// And the Lord did grin, and the people did feast upon the lambs and sloths and carp and anchovies
|
|
/// and orangutans and breakfast cereals and fruit bats and large chu...
|
|
///
|
|
/// And the Lord spake, saying, "First shalt thou depend on the [`smallvec`](https://crates.io/crates/smallvec) crate.
|
|
/// Then, shalt thou keep three inline. No more. No less. Three shalt be the number thou shalt keep inline,
|
|
/// and the number to keep inline shalt be three. Four shalt thou not keep inline, nor either keep inline
|
|
/// thou two, excepting that thou then proceed to three. Five is right out. Once the number three,
|
|
/// being the third number, be reached, then, lobbest thou thy `SmallVec` towards thy heap, who,
|
|
/// being slow and cache-naughty in My sight, shall snuff it."
|
|
///
|
|
/// # Why Three
|
|
///
|
|
/// `StaticVec` is used frequently to keep small lists of items in inline (non-heap) storage in
|
|
/// order to improve cache friendliness and reduce indirections.
|
|
///
|
|
/// The number 3, other than being the holy number, is carefully chosen for a balance between
|
|
/// storage space and reduce allocations. That is because most function calls (and most functions,
|
|
/// for that matter) contain fewer than 4 arguments, the exception being closures that capture a
|
|
/// large number of external variables.
|
|
///
|
|
/// In addition, most script blocks either contain many statements, or just one or two lines;
|
|
/// most scripts load fewer than 4 external modules; most module paths contain fewer than 4 levels
|
|
/// (e.g. `std::collections::map::HashMap` is 4 levels and it is just about as long as they get).
|
|
#[cfg(not(feature = "internals"))]
|
|
type StaticVec<T> = smallvec::SmallVec<[T; STATIC_VEC_INLINE_SIZE]>;
|
|
|
|
/// _(internals)_ Alias to [`smallvec::SmallVec<[T; 3]>`](https://crates.io/crates/smallvec),
|
|
/// which is a [`Vec`] backed by a small, inline, fixed-size array when there are ≤ 3 items stored.
|
|
/// Exported under the `internals` feature only.
|
|
///
|
|
/// # History
|
|
///
|
|
/// And Saint Attila raised the `SmallVec` up on high, saying, "O Lord, bless this Thy `SmallVec`
|
|
/// that, with it, Thou mayest blow Thine allocation costs to tiny bits in Thy mercy."
|
|
///
|
|
/// And the Lord did grin, and the people did feast upon the lambs and sloths and carp and anchovies
|
|
/// and orangutans and breakfast cereals and fruit bats and large chu...
|
|
///
|
|
/// And the Lord spake, saying, "First shalt thou depend on the [`smallvec`](https://crates.io/crates/smallvec) crate.
|
|
/// Then, shalt thou keep three inline. No more. No less. Three shalt be the number thou shalt keep inline,
|
|
/// and the number to keep inline shalt be three. Four shalt thou not keep inline, nor either keep inline
|
|
/// thou two, excepting that thou then proceed to three. Five is right out. Once the number three,
|
|
/// being the third number, be reached, then, lobbest thou thy `SmallVec` towards thy heap, who,
|
|
/// being slow and cache-naughty in My sight, shall snuff it."
|
|
///
|
|
/// # Why Three
|
|
///
|
|
/// `StaticVec` is used frequently to keep small lists of items in inline (non-heap) storage in
|
|
/// order to improve cache friendliness and reduce indirections.
|
|
///
|
|
/// The number 3, other than being the holy number, is carefully chosen for a balance between
|
|
/// storage space and reduce allocations. That is because most function calls (and most functions,
|
|
/// for that matter) contain fewer than 4 arguments, the exception being closures that capture a
|
|
/// large number of external variables.
|
|
///
|
|
/// In addition, most script blocks either contain many statements, or just one or two lines;
|
|
/// most scripts load fewer than 4 external modules; most module paths contain fewer than 4 levels
|
|
/// (e.g. `std::collections::map::HashMap` is 4 levels and it is just about as long as they get).
|
|
#[cfg(feature = "internals")]
|
|
pub type StaticVec<T> = smallvec::SmallVec<[T; STATIC_VEC_INLINE_SIZE]>;
|
|
|
|
/// Number of items to keep inline for [`FnArgsVec`].
|
|
#[cfg(not(feature = "no_closure"))]
|
|
const FN_ARGS_VEC_INLINE_SIZE: usize = 5;
|
|
|
|
/// Inline arguments storage for function calls.
|
|
///
|
|
/// # Notes
|
|
///
|
|
/// Since most usage of this is during a function call to gather up arguments, this is mostly
|
|
/// allocated on the stack, so we can tolerate a larger number of values stored inline.
|
|
///
|
|
/// Most functions have few parameters, but closures with a lot of captured variables can
|
|
/// potentially have many. Having a larger inline storage for arguments reduces allocations in
|
|
/// scripts with heavy closure usage.
|
|
///
|
|
/// Under `no_closure`, this type aliases to [`StaticVec`][crate::StaticVec] instead.
|
|
#[cfg(not(feature = "no_closure"))]
|
|
type FnArgsVec<T> = smallvec::SmallVec<[T; FN_ARGS_VEC_INLINE_SIZE]>;
|
|
|
|
/// Inline arguments storage for function calls.
|
|
/// This type aliases to [`StaticVec`][crate::StaticVec].
|
|
#[cfg(feature = "no_closure")]
|
|
type FnArgsVec<T> = crate::StaticVec<T>;
|
|
|
|
type SmartString = smartstring::SmartString<smartstring::LazyCompact>;
|
|
|
|
// Compiler guards against mutually-exclusive feature flags
|
|
|
|
#[cfg(feature = "no_float")]
|
|
#[cfg(feature = "f32_float")]
|
|
compile_error!("`f32_float` cannot be used with `no_float`");
|
|
|
|
#[cfg(feature = "only_i32")]
|
|
#[cfg(feature = "only_i64")]
|
|
compile_error!("`only_i32` and `only_i64` cannot be used together");
|
|
|
|
#[cfg(feature = "no_std")]
|
|
#[cfg(feature = "wasm-bindgen")]
|
|
compile_error!("`wasm-bindgen` cannot be used with `no-std`");
|
|
|
|
#[cfg(feature = "no_std")]
|
|
#[cfg(feature = "stdweb")]
|
|
compile_error!("`stdweb` cannot be used with `no-std`");
|
|
|
|
#[cfg(target_family = "wasm")]
|
|
#[cfg(feature = "no_std")]
|
|
compile_error!("`no_std` cannot be used for WASM target");
|
|
|
|
#[cfg(not(target_family = "wasm"))]
|
|
#[cfg(feature = "wasm-bindgen")]
|
|
compile_error!("`wasm-bindgen` cannot be used for non-WASM target");
|
|
|
|
#[cfg(not(target_family = "wasm"))]
|
|
#[cfg(feature = "stdweb")]
|
|
compile_error!("`stdweb` cannot be used non-WASM target");
|
|
|
|
#[cfg(feature = "wasm-bindgen")]
|
|
#[cfg(feature = "stdweb")]
|
|
compile_error!("`wasm-bindgen` and `stdweb` cannot be used together");
|