lesleh

Boids Simulation Implementation Plan

For agentic workers: REQUIRED SUB-SKILL: Use superpowers:subagent-driven-development (recommended) or superpowers:executing-plans to implement this plan task-by-task. Steps use checkbox (- [ ]) syntax for tracking.

Goal: Add a Boids flocking simulation playground — 700 agents, spatial grid partitioning for O(n) neighbour lookup, four real-time sliders, dark canvas aesthetic.

Architecture: Simulation logic lives in pure _lib/ modules (spatialGrid.ts, boids.ts) with no React dependencies, making them fully testable. The canvas animation loop runs in a useEffect, reading slider values from a ref each frame so slider changes are instant without causing re-renders. A separate Controls component drives React state which stays in sync with the ref.

Tech Stack: React 19, Next.js 15 App Router, TypeScript, Tailwind CSS, Canvas 2D API, Jest + Happy DOM for tests.

lesleh

export type CamelCase<S extends string> =
  S extends `${infer P1}_${infer P2}${infer P3}`
    ? `${Lowercase<P1>}${Uppercase<P2>}${CamelCase<P3>}`
    : Lowercase<S>;

export type ObjectToCamel<T> = {
  [K in keyof T as CamelCase<string & K>]: T[K] extends Record<string, any>
    ? KeysToCamelCase<T[K]>
    : T[K];
};

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interface Curry {
  <T1, R>(func: (t1: T1) => R): CurriedFunction1<T1, R>;
  <T1, T2, R>(func: (t1: T1, t2: T2) => R): CurriedFunction2<T1, T2, R>;
  <T1, T2, T3, R>(func: (t1: T1, t2: T2, t3: T3) => R): CurriedFunction3<
    T1,
    T2,
    T3,
    R
  >;
  <T1, T2, T3, T4, R>(

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import { renderHook } from '@testing-library/react-hooks';
import useFetch from '../useFetch';

function mockSuccessfulFetch(data) {
  global.fetch = jest.fn().mockResolvedValue({
    json: () => Promise.resolve(data),
  });
}

function mockErrorFetch(error) {

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/* eslint-disable no-restricted-syntax, no-console, no-await-in-loop */
const { promises: fs } = require("fs");
const { exec } = require("child_process");

const TEST_COMMANDS = [
  "yarn check-types",
  "yarn lint",
  "yarn test",
  "yarn build",
];

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const isArray = function (a) {
  return Array.isArray(a);
};

const isObject = function (o) {
  return o === Object(o) && !isArray(o) && typeof o !== 'function';
};

const toCamel = s => (
  s.replace(/([-_][a-z])/ig, $1 => $1.toUpperCase().replace(/[-_]/, ''))

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const toCamel = (s) => {
  return s.replace(/([-_][a-z])/ig, ($1) => {
    return $1.toUpperCase()
      .replace('-', '')
      .replace('_', '');
  });
};

const toSnake = (s) => {
  return s.split(/(?=[A-Z])/).join('_').toLowerCase();

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import React from 'react';

import useWindowEvent from './useWindowEvent';

function Example() {
  useWindowEvent('keydown', (e) => {
    console.log('Pressed', e.key);
  });
  
  return <div>Example</div>;

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const findVideos = () => [...document.querySelectorAll('.pl-video')];

const watchedGreaterThanHalf = (video) => {
  const progressBar = video.querySelector('.resume-playback-progress-bar');
  return progressBar && parseInt(progressBar.style.width) > 50;
}

const removeButton = (video) => x.querySelector('.pl-video-edit-remove');

const click = (button) => button.click();

lesleh

'use strict';

function addHeader(headers, key, value) {
    if (!headers[key.toLowerCase()]) {
        headers[key.toLowerCase()] = [{
            key,
            value,
        }];
    }
}