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_archive/rhai_engine/rhaibook/lib/rhai-rand.md

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+`rhai-rand`: Random Number Generation, Shuffling and Sampling
+=============================================================
+
+{{#include ../links.md}}
+
+`rhai-rand` is an independent Rhai [package] that provides:
+
+* random number generation using the [`rand`](https://crates.io/crates/rand) crate
+* [array] shuffling and sampling
+
+```admonish info.side "Documentation"
+
+See [https://docs.rs/rhai-rand](https://docs.rs/rhai-rand#api) for the list of functions.
+```
+
+> On `crates.io`: [`rhai-rand`](https://crates.io/crates/rhai-rand)
+>
+> On `GitHub`: [`rhaiscript/rhai-rand`](https://github.com/rhaiscript/rhai-rand)
+>
+> Package name: `RandomPackage`
+
+
+Dependency
+----------
+
+`Cargo.toml`:
+
+```toml
+[dependencies]
+rhai = "{{version}}"
+rhai-rand = "0.1"       # use rhai-rand crate
+```
+
+
+Load Package into [`Engine`]
+----------------------------
+
+```rust
+use rhai::Engine;
+use rhai::packages::Package;    // needed for 'Package' trait
+use rhai_rand::RandomPackage;
+
+let mut engine = Engine::new();
+
+// Create new 'RandomPackage' instance
+let random = RandomPackage::new();
+
+// Load the package into the `Engine`
+random.register_into_engine(&mut engine);
+```
+
+
+Features
+--------
+
+|  Feature   | Description                                                  | Default? | Should not be used with Rhai feature |
+| :--------: | ------------------------------------------------------------ | :------: | :----------------------------------: |
+|  `float`   | enables random floating-point number generation              |   yes    |             [`no_float`]             |
+|  `array`   | enables methods for [arrays]                                 |   yes    |             [`no_index`]             |
+| `metadata` | enables [functions metadata] (turns on [`metadata`] in Rhai) |  **no**  |                                      |
+
+~~~admonish example "Example: Working with `no_float` in Rhai"
+
+`Cargo.toml`:
+
+```toml
+[dependencies]
+# Rhai is set for 'no_float', meaning no floating-point support
+rhai = { version="{{version}}", features = ["no_float"] }
+
+# Use 'default-features = false' to clear defaults, then only add 'array'
+rhai-rand = { version="0.1", default-features = false, features = ["array"] }
+```
+~~~