Function downcast_mut 

pub fn downcast_mut<T: ExecutionContext + 'static>(
    context: &mut dyn ExecutionContext,
) -> Option<&mut T>

Attempt to downcast a mutable context reference to a concrete type

This is the mutable version of downcast_ref(). It allows command handlers to modify the context state after downcasting.

Type Parameters

• T - The concrete type to downcast to. Must implement ExecutionContext and have a 'static lifetime.

Arguments

• context - Mutable reference to the execution context trait object

Returns

• Some(&mut T) if the context is of type T
• None if the context is a different type

Example

use dynamic_cli::context::{ExecutionContext, downcast_mut};
use std::any::Any;

struct Counter {
    value: u32,
}

impl ExecutionContext for Counter {
    fn as_any(&self) -> &dyn Any { self }
    fn as_any_mut(&mut self) -> &mut dyn Any { self }
}

fn increment(ctx: &mut dyn ExecutionContext) {
    if let Some(counter) = downcast_mut::<Counter>(ctx) {
        counter.value += 1;
    }
}

Safety

This operation is safe because it uses Rust’s Any::downcast_mut, which performs runtime type checking.