Traceback (most recent call last):


 "/usr/local/bin/ipython", line 8, in <module>

sys.exit(start_ipython())


 "/usr/local/lib/python3.7/site-packages/IPython/__init__.py", line 126, in start_ipython

return launch_new_instance(argv=argv, **kwargs)


 "/usr/local/lib/python3.7/site-packages/traitlets/config/application.py", line 664, in launch_instance

app.start()


 "/usr/local/lib/python3.7/site-packages/IPython/terminal/ipapp.py", line 356, in start

self.shell.mainloop()


 "/usr/local/lib/python3.7/site-packages/IPython/terminal/interactiveshell.py", line 558, in mainloop

self.interact()


 "/usr/local/lib/python3.7/site-packages/IPython/terminal/interactiveshell.py", line 541, in interact

code = self.prompt_for_code()


 "/usr/local/lib/python3.7/site-packages/IPython/terminal/interactiveshell.py", line 469, in prompt_for_code

**self._extra_prompt_options())


 "/usr/local/lib/python3.7/site-packages/prompt_toolkit/shortcuts/prompt.py", line 994, in prompt

return self.app.run(set_exception_handler=set_exception_handler)


 "/usr/local/lib/python3.7/site-packages/prompt_toolkit/application/application.py", line 812, in run

self.run_async(pre_run=pre_run, set_exception_handler=set_exception_handler)


 "/usr/local/Cellar/python/3.7.7/Frameworks/Python.framework/Versions/3.7/lib/python3.7/asyncio/base_events.py", line 587, in run_until_complete

return future.result()


 "/usr/local/lib/python3.7/site-packages/prompt_toolkit/application/application.py", line 614, in run_async

assert not self._is_running, "Application is already running."
AssertionError: Application is already running.

Traceback (most recent call last):


 "bin/osh", line 374, in <module>

sys.exit(main(sys.argv))


 "bin/osh", line 364, in main

return OshMain(main_argv)


 "bin/osh", line 274, in OshMain

InteractiveLoop(opts, ex, c_parser, w_parser, line_reader)


 "bin/osh", line 100, in InteractiveLoop

status, cflow = ex.ExecuteTop(node)


 "/home/icenowy/git-repos/oil/bin/../core/cmd_exec.py", line 635, in ExecuteTop

status, cflow = self.Execute(node)


 "/home/icenowy/git-repos/oil/bin/../core/cmd_exec.py", line 663, in Execute

raise AssertionError('Error evaluating words: %s' % err)
AssertionError: Error evaluating words: ['Undefined variable a', 'Error evaluating word part (SimpleVarSub token:(token id:VSub_Name val:"$a" span_id:0))', 'Error evaluating word (CompoundWord parts:[(SimpleVarSub token:(token id:VSub_Name val:"$a" span_id:0))])']
