How to use deep-equal (Angular 7)

Question

Auto import by VS Code:

import deepEqual = require('deep-equal');

Doesn't work:

error TS1202: Import assignment cannot be used when targeting ECMAScript modules. Consider using 'import * as ns from "mod"', 'import {a} from "mod"', 'import d from "mod"', or another module format instead.

Then I tried to do like this:

import * as deepEqual from 'deep-equal';

error TS2497: Module '"path/@types/deep-equal/index"' resolves to a non-module entity and cannot be imported using this construct.

And like this:

import {deepEqual} from 'deep-equal';

error TS2305: Module '"C:/Projects/ManagerServer/Src-LoyaltyCoin.ManagerServer.Core/ManagerWeb/ClientApp/node_modules/@types/deep-equal/index"' has no exported member 'deepEqual'.

I haven't got ideas how can I import this. If there's no solution for this, please suggest me another library to compare objects for Angular 7.

score 9 · Accepted Answer · 2018-12-05T12:48:55.213

9

Add the script to your angular.json file :

scripts: [
  "node_modules/deep_import/name.of.minified.file.js"
]

And declare a variable in your component :

import { Component } from '@angular/core';
....
declare const deepEqual: any;

Or, you can find typings for it and install them, and import it like any other dependency :

import * as deepEqual from 'deep-equal';

EDIT Just a syntax issue. I suggest you open the repository and see the syntax. The correct one is

import deepEqual from 'deep-equal';

as you can see in this stackbltiz

edited Dec 05 '18 at 12:48

answered Dec 05 '18 at 12:21

1

I already installed the @types/deep-equal, but still have error – Nastya Scherbakova Dec 05 '18 at 12:23
smth like this https://stackblitz.com/edit/angular-qjrh3q?file=src%2Fapp%2Fapp.component.ts – Nastya Scherbakova Dec 05 '18 at 12:43
@NastyaScherbakova Edited my answer, feel free to check it ! – Dec 05 '18 at 12:49
I see but it doesn't work for me for some reason "error TS2304: Cannot find name 'deepEqual'." – Nastya Scherbakova Dec 05 '18 at 12:58
As you can see it works on stackblitz, so you probably have another error. Try re-installing the dependencies, see if it resolves the issue ! – Dec 05 '18 at 12:59
error TS1192: Module '"path/node_modules/@types/deep-equal/index"' has no default export. – Nastya Scherbakova Dec 05 '18 at 13:05
only if I change in library file on 'export default' it works, but it's not a solution :( – Nastya Scherbakova Dec 05 '18 at 13:06
1

Then try `import * as deepEqual from 'deep-equal';` and use it with `deepEqual.deepEqual` – Dec 05 '18 at 13:06
Can someone please clarify to me what this line of code does: ``` declare const deepEqual: any;``` We declare a const deepEqual, but how in world will that const connect to deep-equal library ? – Anton Aug 31 '20 at 14:19
has anyone tried with latest version of deep-equal ? – Sagar Agrawal Apr 16 '21 at 11:26
@user4676340 - Have you tried with latest version of deep-equal ? – Sagar Agrawal Apr 20 '21 at 06:34

cuddlemeister · Answer 2 · 2022-05-04T12:00:35.783

2

You may use fast-deep-equal package. It's included as peer dependency by Angular, but don't forget to add it to regular dependencies. Also, it's the fastest object comparer.

Usage

import equal from 'fast-deep-equal';

equal(a,b); // returns true\false

edited May 04 '22 at 12:00

answered Oct 04 '21 at 15:07

cuddlemeister

1,586
12
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How to use deep-equal (Angular 7)

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