karol-majewski

import * as React from 'react';

// eslint-disable-next-line @typescript-eslint/no-explicit-any
export function withProps<C extends React.ComponentType<any>, D extends Partial<React.ComponentPropsWithoutRef<C>> & JSX.IntrinsicAttributes>(
  Component: C,
  defaults: D
): React.ForwardRefExoticComponent<React.PropsWithoutRef<Omit<React.ComponentProps<C>, keyof D>> & React.RefAttributes<React.ElementRef<C>>> {
  const renderFunction: React.ForwardRefRenderFunction<React.ElementRef<C>, Omit<React.ComponentProps<C>, keyof D>> = (props, ref) => {
    return React.createElement(Component, { ...props, defaults, ref });
  };

karol-majewski

type NonEmptyArray<T> = [T, ...T[]];

const names: NonEmptyArray<string> = ['Sheldon', 'Leonard', 'Penny', 'Rajesh', 'Howard'];

function main(names: NonEmptyArray<string>, n: number){
  let index = n - 1; 

  while (index >= names.length) {
    index = Math.floor((index - names.length) / 2);
  }

karol-majewski

import React from 'react';
import { autobind } from '@typed-decorators/autobind';

class Rolodex<T> {
  index: number;
  length: number;

  constructor(private sequence: NonEmptyArray<T>) {
    this.sequence = sequence;
    this.index = 0;

karol-majewski

type AnyFunction = (...args: any[]) => any;

type FunctionPropertyOf<T> = {
  [P in keyof T]: T[P] extends AnyFunction ? P : never;
}[keyof T];

type MethodOf<T> = {
  [P in keyof T]: T[P] extends (this: ThisType<T[P]>, ...args: any[]) => any ? P : never;
}[keyof T];

karol-majewski

/**
 * When two functions have the same signature, but are not equal.
 * 
 * Fixes the "'T' could be instantiated with a different subtype of constraint" ts(2322) type error.
 * 
 */
type WrapperFunction<T extends AnyFunction> = (...parameters: Parameters<T>) => ReturnType<T>;

/**
 * Prevents stale closures.

karol-majewski

/**
 * Returns a `string` if all parts of the created template string are guaranteed to be defined.
 * If at least one partial string is nullable, the return value will be null.
 *
 * @example
 *
 * ```ts
 * safestring`/api/v1/users/${user?.id}`; // string | null
 * safestring`/api/v1/users/${"15"}`; // string
 * ```

karol-majewski

interface Options {
  /**
   * @default Infinity
   */
  maximumAttempts?: number;
  /**
   * @default 0
   */
  timeoutMs?: number
}

karol-majewski

import LR from 'logrocket';

/**
 * Fails silently if `LogRocket#init` throws.
 *
 * @see https://stackoverflow.com/a/43823282/10325032
 */
export const LogRocket = new Proxy(LR, {
  get(target, property: keyof typeof LR, receiver) {
    if (property === 'init') {

karol-majewski

import React from 'react';

type DeferTypeInference<T> = [T][T extends any ? 0 : never];

interface Props<T extends string> {
  themeMap: Record<T, any>
  defaultTheme?: DeferTypeInference<T>;
}

class ThemeSwitcherProvider<T extends string> extends React.Component<Props<T>> { }

karol-majewski

/**
 * Challenge: given a list of icon names, find icons that exist in sizes 16x16px *and* 24x24px.
 * This is an AND relationship, not an OR relationship.
 * 
 * The solution should be: '16-hamburger' | '16-warning' | '24-hamburger' | '24-warning'.
 */
type IconName =
  | '16-hamburger' // 👈🏻
  | '16-warning'   // 👈🏻
  | '16-foo'