codesnips

generics

rust 
use std::marker::PhantomData;

struct Token<'a> {
    _marker: PhantomData<&'a ()>,
}

PhantomData for zero-cost type-level markers

rust generics phantomdata
by Marcus Chen 1 tab
rust 
use std::collections::HashMap;
use std::hash::Hash;
use std::sync::{Arc, RwLock};

pub struct Memoizer<K, V> {
    store: RwLock<HashMap<K, Arc<V>>>,

Thread-Safe Memoization in Rust with RwLock and OnceCell Sharding

rust concurrency memoization
by codesnips 3 tabs
rust 
trait Container {
    type Item;
    fn get(&self, index: usize) -> Option<&Self::Item>;
}

struct Warehouse {

Associated types in traits for cleaner generics

rust traits generics
by Marcus Chen 1 tab
typescript 
export type EventMap = Record<string, unknown[]>;

type Listener<Args extends unknown[]> = (...args: Args) => void;

export class TypedEmitter<Events extends EventMap> {
  private listeners = new Map<keyof Events, Set<Listener<any>>>();

Type-Safe Event Emitter With Strongly-Typed Listener Payloads in TypeScript

typescript events event-emitter
by codesnips 3 tabs
rust 
use std::fmt::Display;

fn print_it<T: Display>(value: T) {
    println!("Value: {}", value);
}

Trait bounds for generic functions with behavior constraints

rust traits generics
by Marcus Chen 1 tab
rust 
use std::fmt;

#[derive(Debug, Clone, Copy, PartialEq, Eq)]
pub enum OrderState {
    Pending,
    Paid,

Type-State Order Lifecycle Machine With Compile-Time Transition Safety in Rust

state-machine enums type-state
by codesnips 3 tabs
rust 
use std::fmt;
use std::hash::{Hash, Hasher};
use std::marker::PhantomData;
use uuid::Uuid;

pub struct Id<T> {

Type-Safe Entity IDs in Rust with a Zero-Cost Id<T> Newtype

rust newtype type-safety
by codesnips 3 tabs