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<h1 align="center">Dispatcher</h1>
<p align="center">
Mingling's Basic Components
</p>
---
## Intro
`Dispatcher` is a core concept in **Mingling**, used to dispatch user-input arguments to corresponding types, which are then handled by [Chain](pages/2-basic/4-chain) or [Renderer](pages/2-basic/5-renderer).
To define a `Dispatcher`, it is recommended to use the `dispatcher!` macro provided by `mingling_macros`:
```rust
// User input: your_bin hello
// Will access HelloCommand and
// dispatch arguments to HelloEntry
dispatcher!("hello",
HelloCommand => HelloEntry);
// User input: your_bin sub foo
// Will access FooCommand and
// dispatch arguments to FooEntry
dispatcher!("sub.foo",
FooCommand => FooEntry);
// Same as above
dispatcher!("sub.bar",
BarCommand => BarEntry);
```
If you explicitly specify a name in the `gen_program!` macro, for example:
```rust
gen_program!(MyProgram);
```
Then when using the `dispatcher!` macro, you must also explicitly specify the [Program](pages/2-basic/1-program):
```rust
dispatcher!(MyProgram, "hello",
HelloCommand => HelloEntry);
```
**Tips:** Finally, add the `Dispatcher` you created to the [Program](pages/2-basic/1-program):
```rust
#[tokio::main]
async fn main() {
let mut program = ThisProgram::new();
program.with_dispatcher(HelloCommand);
program.with_dispatcher(SubFooCommand);
program.with_dispatcher(SubBarCommand);
program.exec().await;
}
```
## Manual Impl
You can also manually implement the basic `Dispatcher` for more fine-grained control. However, compared to the procmacro, it is more cumbersome and cannot intelligently introduce certain traits based on the state of feature flags.
```rust
// Define AddMemberEntry
// Use the `Groupped` derive to
// mark AddMemberEntry as a member of ThisProgram
#[derive(Debug, Groupped)]
pub struct AddMemberEntry {
// Define arguments to store user input
pub(crate) args: Vec<String>,
}
// Implement the Dispatcher trait
impl Dispatcher<ThisProgram> for AddMemberCommand {
// Return the node name of this Dispatcher
fn node(&self) -> Node {
node!("member.add")
}
// When executing this Dispatcher, output AddMemberEntry
fn begin(&self, args: Vec<String>)
-> ChainProcess<ThisProgram>
{
AnyOutput::new(AddMemberEntry { args }).route_chain()
}
// Used to implement the clone trait for this Dispatcher
fn clone_dispatcher(&self)
-> Box<dyn Dispatcher<ThisProgram>>
{
Box::new(AddMemberCommand)
}
}
```
## 💡 Next Page
> **Basic Component** - Chain [Go](./pages/2-basic/4-chain)
|
