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Comment by AdmiralAsshat | Hacker News Reader

Deep research uses aside, I often prefer to use IPython because it's simply a better shell than the default Python shell. You get basic niceties like tab completion and being able to up-arrow to revise an earlier multi-line command (like a function) without it being an exercise in frustration.

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The multiline history is so important for an interactive shell with a language that considers indentation important.

Indeed. If I could only figure out how to have it automatically run `from math import *` (and then present me with the interactive shell, I could use it as a calculator too.

http://ipython.readthedocs.io/en/stable/config/options/termi...

My problem is that I don't know how to make it accept spaces in the command to be run. This works:

    ipython3 --InteractiveShellApp.exec_lines='["print(2)"]'

This does not work:

    ipython3 --InteractiveShellApp.exec_lines='["from math import *"]'

The latter command results in the following error:

    [TerminalIPythonApp] CRITICAL | The 'exec_lines' trait of a TerminalIPythonApp instance must be a list, but a value of class 'str' (i.e. '["from') was specified.

Rather than fiddling around with quoting bash, you can put the import line in a startup file: http://ipython.readthedocs.io/en/stable/interactive/tutorial...

idk, it works for me:

    $ ipython3 --InteractiveShellApp.exec_lines='["from math import *"]'
    Python 3.6.5 |Anaconda, Inc.| (default, Apr 26 2018, 08:42:37)
    Type 'copyright', 'credits' or 'license' for more information
    IPython 6.4.0 -- An enhanced Interactive Python. Type '?' for help.

    In [1]: sin(5)
    Out[1]: -0.9589242746631385

I see. I have iPython 5.1.0. Maybe there was a bug that has been fixed in yours.

Try this shell script:

    #! /bin/sh
    # This is a bit hacky: we use the -i flag to force the interpreter into 
    # interactive mode after the initial commands are executed.
    # The "proper" way to do this is probably to set up a PYTHONSTARTUP file
    # and put the initial commands in there.
    exec ipython3 --no-banner --no-confirm-exit -i -c '
    from math import *
    import random
    import sys, os, platform
    print("== IPython %s Calculator REPL ==" % platform.python_version())
    '

Thank you for the suggestion! I still get the error, unfortunately:

      File "<ipython-input-1-a0531db54fa8>", line 1
        from
            ^
    SyntaxError: invalid syntax

I shall see if it starts working when I upgrade to a distro with a newer IPython.

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