XmyShell

XmyShell is a shell-like tool built on top of prompt_toolkit which provides a persistent Python runtime. The main process is Python, and shell commands are executed in subprocesses. It provides a persistent Python namespace, inline Python evaluation, and command output capture. It can be useful if you want Python evaluation in a shell or execute shell command conveniently in Python REPL environment.

Get started

Installation

pip install xmyshell

Start

$ xmyshell
XmyShell 0.1.0
Initialized with 296ms.
Username@hostname ➜  ~ 0ms
❯

Learn more through help.

❯ help

Features

Command Line Features

• Persistent Python namespace across commands (variables, imports, functions)
• Expand inline Python expressions within {}, using independent namespace.

❯ mkdir {" ".join(f"test{i}" for i in range(10))}
❯ ls
test0  test1  test2  test3  test4  test5  test6  test7  test8  test9

• Evaluate and print Python expressions with print

❯ print 1 + 1
2

• Execute Python statements with pyexec

❯ pyexec files = [f for f in os.listdir('.') if f.endswith('.py')]
❯ print len(files)
3

• Capture command output into a Python variable with =>.

❯ which python => path
❯ print path
/usr/bin/python
❯ cd {dirname(path)}
❯ pwd
/usr/bin

• Redirect the output of Python commands (print, pyexec) with |>

❯ print "\n".join(str(i) for i in range(100)) |> grep 42 => result
❯ print result
42

• Built-in source command to run python scripts.

❯ which python
/usr/bin/python
❯ source .venv/bin/activate_this.py
❯ which python
/tmp/test/.venv/bin/python

• Built-in export command.

❯ pyexec foo = "foo"
❯ export ENV_VAR={foo}bar
❯ print ENV_VAR
foobar

• Built-in import command.

❯ import numpy as np
❯ from math import *

• Reload with reload command.

❯ reload

• Update xmyshell (optionally to a specific version).

❯ udpate

or

❯ update 0.1.3

• Alias

❯ alias ll='ls -lh'
❯ unalias ll

• Lists, tuples, generators, etc. will be expanded into shell arguments. E.g. {["arg1", "arg2 xxx"]} will be expanded into arg1 'arg2 xxx'

Here is an example (though there are other ways to do this, it is just an example )

❯ pip install {cat("requirements.txt").splitlines()}

• Syntax highlighting via prompt_toolkit
• Powerful auto-completion, history search, and automatic bracket/quote pairing
• Startup configuration: ~/.xmyshell/config.py loaded at launch
• Cross-platform (Windows, Linux, macOS)

Built-in Helper Functions

• getlogin() Returns the current username.

• getcwd() Returns the absolute path of the current working directory.

• dirname(path) Returns the parent directory of a path.

• basename(path) Returns the final component of a path.

• cat(file) Shortcut for open(file).read().

• alias(altname, target) Same as the command.

• unalias(altname) Same as the command.

Reserved global varibles

• exit_code The exit code of the last command.

• exec_duration The duration which last command took.

• SHOW_WELCOME Toggle whether to show welcome message when staring.

• SHELL_CMD Shell command line prefix, defaults to ["cmd", "/c"] on Windows and ["bin/sh", "-c"] on other OS.

• HOME_DIR The home directory, similar to ~.

• PROFILE The path of config file.

Keyboard Shortcuts

• ↑↓ -> Navigate through command history.
• → -> Apply selected history entry to the prompt.
• Ctrl+R -> Reverse incremental searching (history).
• Ctrl+Z -> Undo.
• Ctrl+Y -> Redo.
• Ctrl+D -> Exit XmyShell.
• Auto bracket/parenthesis/quote pairing

Stubs

You can write your xmyshell script with these imports:

from xmyshell.themes import ... # themes
from xmyshell.stubs import ...  # stubs for built-in names

Limitations

XmyShell is Python‑first. This brings power, but also intentional trade‑offs.

• No source for shell scripts — source executes Python files via runpy.run_path(). Shell scripts (e.g., venv/bin/activate) won't work; use activate_this.py instead.

• No deactivate — This is a shell function, not a real command. Virtual environments can be deactivated by reloading environment (reload) or manually restarting a session.

• Shell scripts cannot modify the current environment — Every external command runs in a fresh subprocess; cd, export, aliases, and function definitions inside a script are lost on exit.

• No pipelines between built‑in commands — print and pyexec do not support |. Use Python variables to pass data.

• External command overhead — Each subprocess spawns with minor delays.

Why? XmyShell is NOT a Bash replacement. It's a Python‑native environment for those who want Python's power at the command line.