Pray tell which one of the myriad is the true one?
And do not worry, no one would be rash enough to bring in external dependencies it is just too darn inconvenient.
I should probably drink my coffee before posting, be less grumpy.
Of the languages listed in GP, only Python and JavaScript are scripting languages with REPLs like Bash. Of those two, Python is far more serviceable for what one uses bash for, even in embedded applications (with MicroPython).
Perl, Awk, Ruby, and Lua are also scripting languages one can use in the course of OS scripting. (Your distro probably uses some combination of these, including Python.) Of these, at least Ruby can also be used as a shell.
> Pray tell which one of the myriad is the true one?
You've basically got it, that's just `which python`
I use Python for longer scripts where script maintainability is a priority and external libraries are unnecessary, and as a general shell when I also want my shell to be a calculator, especially when computing on a smartphone (with an appropriate pythonrc).
The key thing is that I already know Python and I find Python's warts more palatable than those on Bash.
What I appreciate about the traditional shell languages is their remarkable stability. Shell scripts written in 2000, or even earlier, are often still able to run today with little or no modification. By contrast, Python applications frequently require recreating a historical runtime environment, including older language versions and dependencies, many of which have accumulated significant security vulnerabilities over time.
Interestingly, apart from the various shell languages, Perl is probably one of the strongest alternatives in this regard. The Perl community has placed a high value on backward compatibility, allowing older code to continue functioning while the language itself remains actively maintained and up to date.
> Comparing the shell to C, Go, Rust, Python, or JavaScript is crazypants. It has a different job than those, so of course it will look and feel different!
The point was just a small one, that Python is not like the others. C, Go, and Rust do not come with REPLs. Node is plausible to use as an OS shell but I've never heard of anyone doing that. Python is the only one of those I've used as a shell or have heard of others using as a shell.
Again, I'm not advocating for Python as a good general-purpose shell. I'm only making the small claim that C, Go, Rust, and (to a smaller extent) JavaScript cannot be be used like bash. Python could be used as a shell.
Python is a full-on programming language. Its REPL is a REPL for that language. Interacting with the OS and filesystem is a niche, tucked away in a corner of the language.
It has has none of the ergonomic affordances needed to be the user interface for interacting with files and processes.
Here are some simple commands:
ls
cd foo
ls
rm bar
cd ../baz
rm bar
echo >readme.txt baz directory
curl -s http://example.com >download
python
>>> ls
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
NameError: name 'ls' is not defined
>>> import system
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
ModuleNotFoundError: No module named 'system'
>>> import os
>>> os.dir.list()
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
AttributeError: module 'os' has no attribute 'dir'
>>> help(os)
>>> os.listdir()
['foo', 'bar', 'baz']
>>> cd foo
File "<stdin>", line 1
cd foo
^
SyntaxError: invalid syntax
>>> chdir("foo")
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
NameError: name 'chdir' is not defined
>>> os.chdir("foo")
>>> os.listdir()
['bar']
>>> os.delete("bar")
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
AttributeError: module 'os' has no attribute 'delete'
>>> os.remove("bar")
>>> os.chdir("../baz")
>>> os.remove("bar")
>>> f = open("readme.txt", "w")
>>> f.write("baz directory")
13
>>> f.close()
>>> import process
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
ModuleNotFoundError: No module named 'process'
>>> import subprocess
>>> subprocess.run("curl", "-s", "http://example.com/")
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
File "/usr/lib/python3.9/subprocess.py", line 505, in run
with Popen(*popenargs, **kwargs) as process:
File "/usr/lib/python3.9/subprocess.py", line 778, in __init__
raise TypeError("bufsize must be an integer")
TypeError: bufsize must be an integer
>>> subprocess.run(["curl", "-s", "http://example.com/"])
...
CompletedProcess(args=['curl', '-s', 'http://example.com/'], returncode=0)
>>> subprocess.run(args=["curl", "-s", "http://example.com/"], capture_output=True)
CompletedProcess(args=['curl', '-s', 'http://example.com/'], returncode=0, stdout=b'...\n', stderr=b'')
>>> p = subprocess.run(args=["curl", "-s", "http://example.com/"], capture_output=True)
>>> fh = open("download", "w")
>>> fh.write(p.stdout)
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
TypeError: write() argument must be str, not bytes
>>> fh = open("download", "wb")
>>> fh.write(p.stdout)
559
>>> fh.close()I would be ready for the window if I had to type
import subprocess; p = subprocess.run(args=["curl", "-s", "http://example.com/"], capture_output=True); fh = open("output", "wb"); fh.write(p.stdout); fh.close()
curl -s http://example.com/ >output
The point I am making is that, of the listed languages, Python is far more comparable to Bash than the others. Suppose you had no choice but to use one of the following executables in place of /usr/bin/bash
- go - gcc - rustc - node - python
You would choose Python, of course. Plausibly node, but certainly not any of the other three.