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Invert Binary Tree

Oct 15, 2022CodeCatch
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More JavaScript Posts

Redux Slice

Mar 11, 2021C S

1 like • 0 views

import { createSlice } from "@reduxjs/toolkit";
const alert = createSlice({
name: "alert",
initialState: {
msg: "",
status: "",
},
reducers: {
set_alert: (state, action) => {
return {
...state,
msg: action.payload.msg,
status: action.payload.status,
};
},
clear_alert: (state, action) => {
return {
...state,
msg: "",
status: "",
};
},
},
});
export default alert.reducer;
const { set_alert, clear_alert } = alert.actions;
export const setAlert = (msg, status) => dispatch => {
dispatch(set_alert({ msg, status }));
setTimeout(() => dispatch(clear_alert()), 4000);
};
export const clearAlert = () => dispatch => {
dispatch(clear_alert());
};

List Largest Files Google Drive

Nov 16, 2023LeifMessinger

0 likes • 6 views

function filePath(file){
let folders = file.getParents();
const parents = [];
function makePathString(folderArray){
let path = "";
folderArray.forEach((folder)=>{
path += "/" + folder.getName();
});
return path;
}
while (folders.hasNext()) {
const folder = folders.next(); //This should hopefully remove that folder from the iterator
parents.unshift(folder);
}
return makePathString(parents);
}
function myFunction() {
const myEmail = Session.getEffectiveUser().getEmail();
Logger.log("My email is " + myEmail);
// Log the name of every file in the user's Drive.
var fileIterator = DriveApp.getFiles();
const files = []; //List of [File, size] entries
const filesMaxSize = 10;
while (fileIterator.hasNext()) {
var file = fileIterator.next();
const owner = file.getOwner();
//Only files I own
if((!(owner)) || (!(owner.getEmail)) || owner.getEmail() != myEmail){
continue;
}
const entry = [file, file.getSize()];
function slideUp(arr, index){
//Let's keep sliding it up so we don't have to sort it at the end.
for(let i = index; i > 0; --i){ //Stops at 1
const nextFile = arr[i-1];
if(nextFile[1] > entry[1]){
break;
}else{
//Swap with the next file to slide the file up
const temp = arr[i];
arr[i] = arr[i - 1];
arr[i - 1] = temp;
}
}
}
if(files.length < filesMaxSize){
files.push(entry);
slideUp(files, files.length - 1);
}else{
if(entry[1] > files[files.length - 1][1]){ //If it's bigger than the smallest file in the list.
files[files.length - 1] = entry; //Replace the smallest file
slideUp(files, files.length - 1); //Slide it up
}
}
}
for(let i = 0; i < filesMaxSize; ++i){
const file = files[i][0];
const size = files[i][1];
Logger.log(size + "\t" + filePath(file) + "/" + file.getName() + "\t" + file.getOwner().getName());
}
}

typewriter-effect in Vanilla JS and React

Jan 25, 2023C S

0 likes • 7 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();
}}
/>

deep merge objects

Nov 19, 2022CodeCatch

0 likes • 3 views

const deepMerge = (a, b, fn) =>
[...new Set([...Object.keys(a), ...Object.keys(b)])].reduce(
(acc, key) => ({ ...acc, [key]: fn(key, a[key], b[key]) }),
{}
);
deepMerge(
{ a: true, b: { c: [1, 2, 3] } },
{ a: false, b: { d: [1, 2, 3] } },
(key, a, b) => (key === 'a' ? a && b : Object.assign({}, a, b))
);
// { a: false, b: { c: [ 1, 2, 3 ], d: [ 1, 2, 3 ] } }

retryPromise.js

Oct 20, 2023LeifMessinger

0 likes • 18 views

//Retries maxRetries number of times, meaning that if you have 0, then it'll run the function once.
async function retryPromise(promiseFn, maxRetries = 3, delayOffset = 0, delayRandomRange = 0) {
return new Promise((resolve, reject) => {
promiseFn()
.then(resolve, (error) => { //On error
if (maxRetries <= 0) {
return reject(error);
} else {
if(delayRandomRange * Math.random() + delayOffset < 1.0){
return retryPromise(promiseFn, maxRetries - 1, delayOffset, delayRandomRange).then(resolve, reject);
}else{
return new Promise((resolveTwo, rejectTwo) => {
setTimeout(() => {
return retryPromise(promiseFn, maxRetries - 1, delayOffset, delayRandomRange).then(resolveTwo, rejectTwo);
}, delayRandomRange * Math.random() + delayOffset);
}).then(resolve, reject);
}
}
});
});
}
//Tests for that function.
//Returns a function that will fail numTimes times, then will return aValue
function functionThatReturnsAFunctionThatFailsACoupleTimes(numTimes, aValue){
return async function(){
if(numTimes == 0){
return aValue;
}
numTimes--;
throw false;
};
}
const SMALL_NUMBER = 10;
function testTest(failNumberOfTimes){
let functionThatFailsACoupleTimes = functionThatReturnsAFunctionThatFailsACoupleTimes(failNumberOfTimes, true);
//Test my test
for(let i = 0; i < (failNumberOfTimes * 2); ++i){
function evalTest(val){
let testTestFailedReason = "";
if(val === undefined){
testTestFailedReason = "Test test returned undefined for some reason.";
}
if((i + 1) > failNumberOfTimes){
if(val === true){
//We're good
}else{
testTestFailedReason = "Test test didn't return true when it should have.";
}
}else{
if(val === false){
//We're good
}else{
testTestFailedReason = "Test test didn't return false when it should have.";
}
}
testTestFailedReason = testTestFailedReason || "Test test passed test case";
console.log(testTestFailedReason, "at index", i, "where the function returned", val);
}
functionThatFailsACoupleTimes().then(evalTest, evalTest)
};
}
testTest(SMALL_NUMBER);
let testCaseCounter = 1;
const throwsNoError = [
(val)=>{
if(val == true){
console.log("Passed test case " + (testCaseCounter++));
}else{
console.error("Unexpected return value", val);
}
},
()=>{
console.error("It wasn't supposed to fail!")
}
]
const throwsError = [
(val)=>{
console.error("It wasn't supposed to succeed!", val);
},
(val)=>{
if(val == false){
console.log("Passed test case " + (testCaseCounter++));
}else{
console.error("Unexpected return value", val);
}
}
];
//Runs SMALL_NUMBER times, because SMALL_NUMBER - 1 is the number of retries after the first one
let functionThatFailsACoupleTimes = functionThatReturnsAFunctionThatFailsACoupleTimes(SMALL_NUMBER - 1, true);
retryPromise(functionThatFailsACoupleTimes, SMALL_NUMBER - 1).then(...throwsNoError)
functionThatFailsACoupleTimes = functionThatReturnsAFunctionThatFailsACoupleTimes(SMALL_NUMBER - 1, true);
//Runs SMALL_NUMBER - 1 times, because SMALL_NUMBER - 2 is the number of retries after the first one
retryPromise(functionThatFailsACoupleTimes, SMALL_NUMBER - 2).then(...throwsError)
//Testing the delay. You'll have to wait a bit too.
functionThatFailsACoupleTimes = functionThatReturnsAFunctionThatFailsACoupleTimes(SMALL_NUMBER - 1, true);
//Runs SMALL_NUMBER times, because SMALL_NUMBER - 1 is the number of retries after the first one
retryPromise(functionThatFailsACoupleTimes, SMALL_NUMBER - 1, 500, 500).then(...throwsNoError)
functionThatFailsACoupleTimes = functionThatReturnsAFunctionThatFailsACoupleTimes(SMALL_NUMBER - 1, true);
//Runs SMALL_NUMBER - 1 times, because SMALL_NUMBER - 2 is the number of retries after the first one
retryPromise(functionThatFailsACoupleTimes, SMALL_NUMBER - 2, 500, 500).then(...throwsError)

Composing components

Nov 19, 2022CodeCatch

0 likes • 3 views

function Welcome(props) {
return <h1>Hello, {props.name}</h1>;
}
function App() {
return (
<div>
<Welcome name="Sara" />
<Welcome name="Cahal" />
<Welcome name="Edite" />
</div>
);
}
ReactDOM.render(
<App />,
document.getElementById('root')
);