79 lines
1.9 KiB
Markdown
79 lines
1.9 KiB
Markdown
# Rhai Derive Macros
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This crate provides procedural macros to simplify the integration of Rust types with the Rhai scripting engine.
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## `RhaiApi` Derive Macro
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The `RhaiApi` macro automatically generates a Rhai module with a fluent, builder-style API for your Rust structs. This allows you to create and modify your structs in Rhai scripts using chained method calls.
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### How It Works
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When you derive `RhaiApi` on a struct, the macro generates:
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1. A new Rust module named `{struct_name}_rhai_dsl`.
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2. A Rhai `export_module` within that module named `generated_rhai_module`.
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3. A `new_{struct_name}()` function to create a new instance of your struct.
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4. Setter functions for each field in your struct, allowing for method chaining.
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5. An `id()` function to retrieve the object's ID.
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### Example
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**Rust Struct Definition:**
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```rust
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use derive::RhaiApi;
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#[derive(RhaiApi, Clone)]
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pub struct Product {
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pub id: i64,
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pub name: String,
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pub price: f64,
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}
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```
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**Generated Rhai API Usage:**
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```rhai
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// Import the generated module
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import product_rhai_dsl::generated_rhai_module as product_api;
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// Use the fluent API to build a new product
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let my_product = product_api::new_product()
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.id(1)
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.name("Awesome Gadget")
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.price(99.99);
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print(my_product.id()); // prints 1
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```
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## `FromVec` Derive Macro
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The `FromVec` macro is a utility for tuple structs that contain a single field. It implements the `From<T>` trait, where `T` is the inner type, allowing for seamless conversions.
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### Example
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**Rust Struct Definition:**
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```rust
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use derive::FromVec;
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#[derive(FromVec)]
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pub struct MyVec(Vec<u8>);
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```
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**Usage:**
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```rust
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let data = vec![1, 2, 3];
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let my_vec = MyVec::from(data);
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```
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## Usage
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To use these macros in your project, add this crate as a dependency in your `Cargo.toml` file:
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```toml
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[dependencies]
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derive = { path = "../path/to/rhailib/src/derive" }
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```
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