Crate stack_dst

Stack-based Dynamically-Sized Types

The StackDST type provides a fixed size (7 word in the current version) buffer in which a trait object or array can be stored, without resorting to a heap allocation.

Examples

An unboxed any

As a quick example - The following wraps a 64-bit integer up in a StackDST using the Any trait.

use stack_dst::StackDST;
use std::any::Any;

let dst = StackDST::<Any>::new(1234u64).ok().expect("Integer did not fit in allocation");
println!("dst as u64 = {:?}", dst.downcast_ref::<u64>());
println!("dst as i8 = {:?}", dst.downcast_ref::<i8>());

Stack-allocated closure!

The following snippet shows how small ('static) closures can be returned using StackDST

use stack_dst::StackDST;
 
fn make_closure(value: u64) -> StackDST<FnMut()->String> {
    StackDST::new(move || format!("Hello there! value={}", value)).ok().expect("Closure doesn't fit")
}
let mut closure = make_closure(666);
assert_eq!( (&mut *closure)(), "Hello there! value=666" );

Structs

StackDSTA

Traits

DataBuf

Trait used to represent the data buffer for StackDSTA.

Type Definitions

StackDST

Stack-allocated DST