Surya JS Journey

Learn JavaScript through concepts, code, and guided practice.

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

Challenge Playground

Spot shared object mutation

Update the copy logic so the first log prints `1` and the second log prints `2`. Do not change the final two `console.log` calls.

Mode

Challenge mode

Run code, inspect output, and reset instantly.

Source

Loaded from a challenge

Starter code is loaded directly into the editor.

File

reference-mutation.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.

Challenge Workspace

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

Editor

7 lines

Output

0 entries

Mode

challenge

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.

reference-mutation.js

7 linesMonaco Editor

Editor Actions

Run your solution and compare the result with the expected challenge output.

Console0 entries

Run the code to see output here.

Challenge Result

Run the code to check whether your solution matches the expected outcome.

Expected Output

1
2

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