codesnips

memoization

ruby 
module CollectionCacheKey
  extend ActiveSupport::Concern

  def cache_key_for(scope)
    relation = scope.respond_to?(:all) ? scope.all : scope
    model = relation.klass

Deterministic Cache Keys for Collections

rails caching activerecord
by codesnips 3 tabs
typescript 
import { useState, useMemo, useCallback } from 'react'
import { Post } from '@/types'
import { PostCard } from './PostCard'

interface FilteredPostsProps {
  posts: Post[]

Memoization in React with useMemo and useCallback

react performance memoization
by Maya Patel 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
typescript 
type Loader<T> = () => Promise<T>;

interface Entry<T> {
  value: T;
  expiresAt: number;
}

TTL Cache With In-Flight Request Deduplication for Async Calls

caching async deduplication
by codesnips 4 tabs
ruby 
class RevenueStat
  DEFAULT_RANGE = 30.days

  def initialize(account, range: DEFAULT_RANGE)
    @account = account
    @range = range

Memoized Query Object for a Cached Dashboard Stat in Rails

rails activerecord query-object
by codesnips 3 tabs
typescript 
import { useMemo } from "react";

export type SortDir = "asc" | "desc";
export interface SortConfig<T> {
  key: keyof T;
  dir: SortDir;

Memoized Async Search With a Cached Selector Hook in React

react hooks usememo
by codesnips 3 tabs
erb 
{% load cache %}
<section class="dashboard">
  <h1>{{ team.name }} — Overview</h1>

  {% cache 3600 team_order_stats team.id stats_version %}
    <div class="stat-grid">

Cache an Expensive Dashboard Fragment with Django's Template Cache Tag and Signal-Based Invalidation

django caching template-cache
by codesnips 3 tabs
typescript 
import { startOfDay, isToday, isYesterday, format } from 'date-fns';

export interface ChatMessage {
  id: string;
  senderId: string;
  senderName: string;

Group Chat Messages by Day with a Memoized Selector in React

react typescript selectors
by codesnips 3 tabs
ruby 
module Cacheable
  extend ActiveSupport::Concern

  def cache_query(prefix, scope, expires_in: 15.minutes)
    key = [prefix, cache_version_token(scope)].join("/")

Targeted Query Caching for Expensive Endpoints

rails activerecord performance
by codesnips 3 tabs
ruby 
class Current < ActiveSupport::CurrentAttributes
  attribute :user, :request_id

  def permissions
    @permissions ||= PermissionSet.new(user)
  end

Memoizing Computed User Permissions Per Request with Current Attributes in Rails

rails authorization caching
by codesnips 4 tabs
javascript 
'use strict';

function dedupeAsync(producer, keyFn) {
  const pending = new Map();
  const resolveKey = keyFn || ((...args) => JSON.stringify(args));

Deduplicate Concurrent Async Calls With a Promise Cache in Node.js

nodejs async promises
by codesnips 3 tabs
ruby 
class PriceBreakdown < Struct.new(:subtotal_cents, :discount_cents, :tax_cents, keyword_init: true)
  def initialize(*)
    super
    freeze
  end

Memoizing a Pricing Breakdown as an Immutable Value Object in Rails

rails memoization value-object
by codesnips 3 tabs