Out of your way, the way you like it.
Tabs that come back after you quit, code files in and out, your layout and your look, and a window that can stay on top.
01
Tabs that come back
Each tab holds one Snippet. Quit whenever you like: the tabs come back with their code, and ⌘⇧T reopens one you closed.
A small demo, so there is something to run. Clear it and write your own.
import { useEffect, useState } from "react"
One file is one component: its script, its markup and its styles.
1⌄// A small demo, so there is something to run. Clear it and write your own.
2⌄// A `//?` after a line shows what it came to; hover the value for every pass.
3⌄const scores = [12, 7, 30, 4]
4⌄
5⌄let total = 0
6⌄for (const score of scores) {
7⌄ total += score //? → 53
8⌄}
9⌄
10⌄console.log("total", total)
11⌄console.log("highest", Math.max(...scores))
12⌄
total 53
L10highest 30
L11Done in 4ms·code changed since·Runs as you type
Close
Close 2 other tabs
Close tab to the right
02
Open and save code files
Drop a .js, .ts, .html, .vue or .svelte file on the window to open a copy in a tab. Save to File writes a tab to a file.
A small demo, so there is something to run. Clear it and write your own.
1⌄// A small demo, so there is something to run. Clear it and write your own.
2⌄// A `//?` after a line shows what it came to; hover the value for every pass.
3⌄const scores = [12, 7, 30, 4]
4⌄
5⌄let total = 0
6⌄for (const score of scores) {
7⌄ total += score //? → 53
8⌄}
9⌄
10⌄console.log("total", total)
11⌄console.log("highest", Math.max(...scores))
12⌄
total 53
L10highest 30
L11Done in 4ms·code changed since·Runs as you type
Drop to open as a new tab
03
Side by side or stacked
Put the code beside its output or above it, or show only one side.
A small demo, so there is something to run. Clear it and write your own.
1⌄// A small demo, so there is something to run. Clear it and write your own.
2⌄// A `//?` after a line shows what it came to; hover the value for every pass.
3⌄const scores = [12, 7, 30, 4]
4⌄
5⌄let total = 0
6⌄for (const score of scores) {
7⌄ total += score //? → 53
8⌄}
9⌄
10⌄console.log("total", total)
11⌄console.log("highest", Math.max(...scores))
12⌄
total 53
L10highest 30
L11Done in 4ms·code changed since·Runs as you type
Show
Code and output
Code only
Output only
Panes
Side by side
Stacked
Output first
Keep on topStays above other apps’ windows, to watch the output while you work elsewhere.
Drag to resize. Double-click to reset.
04
Keep JSpark on top
Keep JSpark above your editor or browser, so the output stays in view while you work.
A small demo, so there is something to run. Clear it and write your own.
1⌄// A small demo, so there is something to run. Clear it and write your own.
2⌄// A `//?` after a line shows what it came to; hover the value for every pass.
3⌄const scores = [12, 7, 30, 4]
4⌄
5⌄let total = 0
6⌄for (const score of scores) {
7⌄ total += score //? → 53
8⌄}
9⌄
10⌄console.log("total", total)
11⌄console.log("highest", Math.max(...scores))
12⌄
total 53
L10highest 30
L11Done in 4ms·code changed since·Runs as you type
Show
Code and output
Code only
Output only
Panes
Side by side
Stacked
Output first
Keep on topStays above other apps’ windows, to watch the output while you work elsewhere.
Drag to resize. Double-click to reset.
05
Your look
Night or Day, code colours to go with each, and your text size.
A small demo, so there is something to run. Clear it and write your own.
1⌄// A small demo, so there is something to run. Clear it and write your own.
2⌄// A `//?` after a line shows what it came to; hover the value for every pass.
3⌄const scores = [12, 7, 30, 4]
4⌄
5⌄let total = 0
6⌄for (const score of scores) {
7⌄ total += score //? → 53
8⌄}
9⌄
10⌄console.log("total", total)
11⌄console.log("highest", Math.max(...scores))
12⌄
total 53
L10highest 30
L11Done in 4ms·code changed since·Runs as you type
06
As many tabs as you like JSpark+
JSpark keeps up to 3 Snippets open at once. JSpark+ has no limit.
scores
prices
counter
dates
todo list
regex
chart
1⌄// A small demo, so there is something to run. Clear it and write your own.
2⌄// A `//?` after a line shows what it came to; hover the value for every pass.
3⌄const scores = [12, 7, 30, 4]
4⌄
5⌄let total = 0
6⌄for (const score of scores) {
7⌄ total += score //? → 53
8⌄}
9⌄
10⌄console.log("total", total)
11⌄console.log("highest", Math.max(...scores))
12⌄
total 53
L10highest 30
L11Done in 4ms·code changed since·Runs as you type
07
Every look JSpark+
Every app theme and code colour, JetBrains Mono, and Fira Code with ligatures.
A small demo, so there is something to run. Clear it and write your own.
1⌄// A small demo, so there is something to run. Clear it and write your own.
2⌄// A `//?` after a line shows what it came to; hover the value for every pass.
3⌄const scores = [12, 7, 30, 4]
4⌄
5⌄let total = 0
6⌄for (const score of scores) {
7⌄ total += score //? → 53
8⌄}
9⌄
10⌄console.log("total", total)
11⌄console.log("highest", Math.max(...scores))
12⌄
total 53
L10highest 30
L11Done in 4ms·code changed since·Runs as you type
Good to know
- Updates, in both editions
- JSpark updates itself, and every new version reaches everyone, whichever edition they have.
- Shortcuts
- Most commands have one, such as ⌘T for a new Snippet and ⌘1 to ⌘9 to switch tabs.
- Settings you can search
- Press ⌘F in Settings to find a setting.
- Files are copies
- JSpark never writes back to a file it opened. In JSpark, an opened file counts toward the 3 tabs.
Read the Tabs docs Layout Themes and fonts Open and save files Keyboard shortcuts All features
Quit any time. Your tabs are there when you return.
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Windows: coming later