zxel

zxel is an interactive terminal shell for JavaScript runtimes with syntax highlight and zx utilities.

Usage

Prerequisites: Node (version 18 or above)

npx zxel

Alternatively, with Bun.

bunx zxel

Features

• Read-eval-print-loop of JavaScript expression
• Syntax highlight using emphasize
• Keyboard shortcuts similar to readline
• Top-level await
• Globals from zx
• Runs with Bun or Deno if installed

Environment

Assign variables on this to make it available for subsequent lines of code.

this.a = 123

Then it can be used as a global variable.

a + 456

Using let or const to define a variable doesn't work currently, because every line is evaluated in its own function scope. This might change in the future if the input code is parsed and processed.

Global utilities like fs and glob are also defined on this. For example, to see a list:

Object.keys(this).sort()

Globals

Utilities from zx are defined as global variables.

• $ - Run shell command with return value

  const text = await $`cat readme.md`
  const files = (await $`ls -1`).split('\n')

• $see - Run shell command with console output

  await $see`ls -1`

• cd - Change directory
• fetch - Fetch
• fs - File system utilities from fs-extra
• glob - Pattern match files using globby

  for (const file of await glob('*.txt')) {
    console.log(file)
  }

• globDir - Pattern match directories
• os - OS info from os
• path - Path utilities from path

Also globals from Node; or globals from Bun with Database and db, a database instance at ~/.zxel/db.sqlite.

Modules can be dynamically imported with await import().

Keyboard shortcuts

Shortcut	Action
Enter	Run code
Escape	Cancel
→	Forward one character
Ctrl+→	Forward one word
←	Backward one character
Ctrl+←	Backward one word
Home, Ctrl+A	Beginning of line
End, Ctrl+E	End of line
↓	Next line in history
↑	Previous line in history
Ctrl+C	Exit shell
Backspace	Delete previous character
Delete	Delete next character
Ctrl+L	Clear screen

TODO

• Multiline mode

References

• ANSI Escape Sequences