LWC File structure with many modulated JS files

Following snippets will help you to understand the file structure and usage.

File Structure

       lwc
             ---- lwc_pd_comp
                                           -------lwc_pd_comp.html
                                           -------lwc_pd_comp.js
                                           -------lwc_pd_comp.js-meta.xml
                                           -------helper.js

	export function isFunction(value) {
	return 'Test'+ value;
	}

view raw helper.js hosted with ❤ by GitHub

	<template>
	<lightning-card title="Details" icon-name="custom:custom14">
	<div class="slds-m-around_medium">
	<p>Hello, {greeting}! {result}!</p>
	<lightning-input label="Name" value={greeting} onchange={changeHandler}></lightning-input>
	</div>
	</lightning-card>
	</template>

view raw lwc_pd_comp.html hosted with ❤ by GitHub

	import { LightningElement, track } from 'lwc';
	import { isFunction } from './helper';
	export default class HelloWorld extends LightningElement {
	@track greeting = 'world';
	@track result = 'init';
	changeHandler(event) {
	this.greeting = event.target.value;
	// Call the imported library function
	this.result = isFunction(' ' + event.target.value + ' ;');
	}
	}

view raw lwc_pd_comp.js hosted with ❤ by GitHub

	<?xml version="1.0" encoding="UTF-8"?>
	<LightningComponentBundle xmlns="http://soap.sforce.com/2006/04/metadata" fqn="helloWorld">
	<apiVersion>45.0</apiVersion>
	<isExposed>true</isExposed>
	<targets>
	<target>lightning__AppPage</target>
	<target>lightning__RecordPage</target>
	<target>lightning__HomePage</target>
	</targets>
	</LightningComponentBundle>

view raw lwc_pd_comp.js-meta.xml hosted with ❤ by GitHub