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const pattern = 'abcdefgh';

for (const [currentChar, nextChar] of pattern.split('').reduce((acc,value,idx,arr)=>{const entry = [value]; if ( arr.length > idx + 1 ) entry.push(arr[idx+1]); acc.push(entry); return acc},[])) {
    console.log(currentChar,nextChar)
}
/**
a b
b c
c d
d e

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const {readFile} = require("fs").promises;
const run = async () => {
    const loadCSV = async (fileName ) => {
        const contents = await readFile(fileName, 'utf8');
        const lines = contents
            .split('\n')
            .filter(Boolean)
            .map((t)=>t.trim()) // remove leading and trailing \r for non-utf8 files
            .map((line)=>{

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How to split a file on lines

Use case, you have a csv file, you want it to be split by 100 line numbers into files.. The onlys ide effect is you get sample-aa, sample-ab.... no extension

split -l 100 sample.csv sample-

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const AWS = require('aws-sdk')
const fs = require("fs").promises;
const {join} = require('path')
const path = require("path");
const { createReadStream, createHash } = require('crypto')

const credentials = {
    accessKeyId: process.env.AWS_ACCESS_KEY_ID || 'test',
    secretAccessKey: process.env.AWS_SECRET_KEY || 'test' ,
}

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git diff --name-only HEAD

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In Node.js, the process.exit() method is used to exit the current Node.js process with a given exit code. The number argument passed to process.exit() represents the exit code that the Node.js process will exit with.

Here are the commonly used exit codes and their meanings:

• 0: The process exits successfully without any errors.
• 1: The process exits due to an uncaught exception.
• 2: The process exits due to a misconfiguration or missing file.
• 3: The process exits due to a fatal error.

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Process NextTick and SetImmediate

In Node.js, process.nextTick() is a method that allows you to schedule a function to be executed on the next iteration of the event loop. It is often used to defer the execution of a function until after the current function has completed.

The process.nextTick() method is similar to setImmediate(), but with a few key differences. While setImmediate() schedules a callback to run in the next iteration of the event loop, process.nextTick() schedules a callback to run at the end of the current iteration of the event loop, before any I/O operations.

Here is an example of how process.nextTick() can be used:

console.log('start');

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Stream

From NodeJS Docs

Stability: 2 - Stable

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// BUFFER

// Load the whole content into a buffer/ into memory once before wrting it out to user

const http = require("http");
const media = "./testvid.mp4";
const fs = require("fs");

http
  .createServer((req, res) => {

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How to find all the files that changed in a given branch since it was cut

1. you will need the HashCode of when the branch was cut.
2. then check out the branch..
3. from the command line execute the following

git diff --name-only <hashcode>..<branch>