//! | `no_stdlib` | Exclude the standard library of utility functions in the build, and only include the minimum necessary functionalities. Standard types are not affected. |
//! | `unchecked` | Exclude arithmetic checking (such as overflows and division by zero). Beware that a bad script may panic the entire system! |
//! | `no_function` | Disable script-defined functions if not needed. |
//! | `no_index` | Disable arrays and indexing features if not needed. |
//! | `no_object` | Disable support for custom types and objects. |
//! | `no_float` | Disable floating-point numbers and math if not needed. |
//! | `no_optimize` | Disable the script optimizer. |
//! | `only_i32` | Set the system integer type to `i32` and disable all other integer types. `INT` is set to `i32`. |
//! | `only_i64` | Set the system integer type to `i64` and disable all other integer types. `INT` is set to `i64`. |
//! | `no_std` | Build for `no-std`. Notice that additional dependencies will be pulled in to replace `std` features. |
//! | `sync` | Restrict all values types to those that are `Send + Sync`. Under this feature, `Engine`, `Scope` and `AST` are all `Send + Sync`. |
//!
//! [Check out the README on GitHub for details on the Rhai language!](https://github.com/jonathandturner/rhai)