• Nov 19, 2022 •CodeCatch
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const copyToClipboard = str => { const el = document.createElement('textarea'); el.value = str; el.setAttribute('readonly', ''); el.style.position = 'absolute'; el.style.left = '-9999px'; document.body.appendChild(el); const selected = document.getSelection().rangeCount > 0 ? document.getSelection().getRangeAt(0) : false; el.select(); document.execCommand('copy'); document.body.removeChild(el); if (selected) { document.getSelection().removeAllRanges(); document.getSelection().addRange(selected); } }; copyToClipboard('Lorem ipsum'); // 'Lorem ipsum' copied to clipboard.
arr = [] // empty array const isEmpty = arr => !Array.isArray(arr) || arr.length === 0; // Examples isEmpty([]); // true isEmpty([1, 2, 3]); // false
• Feb 5, 2021 •LeifMessinger
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class Timer{ start(){ this.startTime = Date.now(); } stop(){ const dt = Date.now() - this.startTime; console.log(dt); return dt; } getExecTime(fun, asynchronous){ return asynchronous ? this.getAsyncExecTime(fun) : this.getSyncExecTime(fun); } getSyncExecTime(fun){ this.start(); fun(); return this.stop(); } async getAsyncExecTime(fun){ this.start(); await fun(); return this.stop(); } static average(fun, numTimes, asynchronous = false){ const times = []; const promises = []; let timer = new Timer(); if(asynchronous){ for(let i = 0; i < numTimes; i++){ timer.getAsyncExecTime(fun); } }else{ for(let i = 0; i < numTimes; i++){ timer.getSyncExecTime(fun); } } return (times => times.reduce(((sum, acc) => sume + acc), 0) / times.length); } static async timeAsync(fun, numTimes){ if(numTimes <= 1) return new Timer().getAsyncExecTime(fun); const promises = []; let timer = new Timer(true); for(let i = 0; i < numTimes; i++){ promises.push(fun().catch((e)=>{})); } try{ await Promise.all(promises).catch((e)=>{}); }catch(e){ //do absolutely nothing } return timer.stop(); } constructor(start = false){ if(start) this.start(); } }
• Mar 11, 2021 •C S
import { configureStore } from "@reduxjs/toolkit"; import { combineReducers } from "redux"; import profile from "./profile"; import auth from "./auth"; import alert from "./alert"; const reducer = combineReducers({ profile, auth, alert, }); const store = configureStore({ reducer }); export default store;
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class LinkedList { constructor() { this.nodes = []; } get size() { return this.nodes.length; } get head() { return this.size ? this.nodes[0] : null; } get tail() { return this.size ? this.nodes[this.size - 1] : null; } insertAt(index, value) { const previousNode = this.nodes[index - 1] || null; const nextNode = this.nodes[index] || null; const node = { value, next: nextNode }; if (previousNode) previousNode.next = node; this.nodes.splice(index, 0, node); } insertFirst(value) { this.insertAt(0, value); } insertLast(value) { this.insertAt(this.size, value); } getAt(index) { return this.nodes[index]; } removeAt(index) { const previousNode = this.nodes[index - 1]; const nextNode = this.nodes[index + 1] || null; if (previousNode) previousNode.next = nextNode; return this.nodes.splice(index, 1); } clear() { this.nodes = []; } reverse() { this.nodes = this.nodes.reduce( (acc, { value }) => [{ value, next: acc[0] || null }, ...acc], [] ); } *[Symbol.iterator]() { yield* this.nodes; } } const list = new LinkedList(); list.insertFirst(1); list.insertFirst(2); list.insertFirst(3); list.insertLast(4); list.insertAt(3, 5); list.size; // 5 list.head.value; // 3 list.head.next.value; // 2 list.tail.value; // 4 [...list.map(e => e.value)]; // [3, 2, 1, 5, 4] list.removeAt(1); // 2 list.getAt(1).value; // 1 list.head.next.value; // 1 [...list.map(e => e.value)]; // [3, 1, 5, 4] list.reverse(); [...list.map(e => e.value)]; // [4, 5, 1, 3] list.clear(); list.size; // 0
• Jan 25, 2023 •C S
0 likes • 13 views
// Vanilla JS Solution: var app = document.getElementById('app'); var typewriter = new Typewriter(app, { loop: true }); typewriter .typeString("I'm John and I'm a super cool web developer") .pauseFor(3000) .deleteChars(13) // "web developer" = 13 characters .typeString("person to talk with!") // Will display "I'm John and I'm a super cool person to talk with!" .start(); // React Solution: import Typewriter from 'typewriter-effect'; <Typewriter options={{ loop: true }} onInit={typewriter => { typewriter .typeString("I'm John and I'm a super cool web developer") .pauseFor(3000) .deleteChars(13) // "web developer" = 13 characters .typeString("person to talk with!") // Will display "I'm John and I'm a super cool person to talk with!" .start(); }} />