Surya JS Journey

Learn JavaScript through concepts, code, and guided practice.

A focused workspace for concept study, interactive examples, visual explanations, and challenge solving.

Concept Playground

Spread and Rest

Spread syntax is used to copy or combine arrays and objects, and rest syntax is used to gather remaining values in function parameters or destructuring. They look similar but solve opposite problems. These operators appear everywhere in modern JavaScript code.

Mode

Practice mode

Run code, inspect output, and reset instantly.

Source

Loaded from a concept

Starter code is loaded directly into the editor.

File

spread-rest.js

Same code, editable immediately in the browser.

Workspace Flow

1. Edit the snippet

Change the code freely to test ideas and edge cases.

2. Run and inspect

Use the output panel to confirm behavior and catch runtime errors.

3. Reset or continue

Restore the starter or branch into your own experiment.

Practice Workspace

spread-rest.js

Edit the code, run it in the browser, and inspect the console output below. Reset restores the original snippet for this page.

Editor

9 lines

Output

0 entries

Mode

practice

Workspace Notes

Changes stay local until you run the code. Reset restores the original snippet immediately for another pass.

Live editing

Safe to change before every run.

Fast reset

Return to the original starter instantly.

spread-rest.js

9 linesMonaco Editor

Editor Actions

Use the editor to explore the example, then run it to inspect the console.

Console0 entries

Run the code to see output here.

Expected Output

1,2,3
4,5

Want a blank workspace again? Go back to the default playground.