How do I export the output of Python's built-in help() function

Question

I\'ve got a python package which outputs considerable help text from: help(package)

I would like to export this help text to a file, in the format in w

Answer 1

In Windows, just open up a Windows Command Line window, go to the Lib subfolder of your Python installation, and type

python pydoc.py moduleName.memberName > c:\myFolder\memberName.txt

to put the documentation for the property or method memberName in moduleName into the file memberName.txt. If you want an object further down the hierarchy of the module, just put more dots. For example

python pydoc.py wx.lib.agw.ultimatelistctrl > c:\myFolder\UltimateListCtrl.txt

to put the documentation on the UltimateListCtrl control in the agw package in the wxPython package into UltimateListCtrl.txt.

Answer 2

This is a bit hackish (and there's probably a better solution somewhere), but this works:

import sys
import pydoc

def output_help_to_file(filepath, request):
    f = open(filepath, 'w')
    sys.stdout = f
    pydoc.help(request)
    f.close()
    sys.stdout = sys.__stdout__
    return

And then...

>>> output_help_to_file(r'test.txt', 're')

Answer 3

If you do help(help) you'll see:

Help on _Helper in module site object:

class _Helper(__builtin__.object)
 |  Define the builtin 'help'.
 |  This is a wrapper around pydoc.help (with a twist).

[rest snipped]

So - you should be looking at the pydoc module - there's going to be a method or methods that return what help(something) does as a string...

Answer 4

pydoc already provides the needed feature, a very well-designed feature that all question-answering systems should have. The pydoc.Helper.init has an output object, all output being sent there. If you use your own output object, you can do whatever you want. For example:

class OUTPUT():

def __init__(self):
    self.results = []
def write(self,text):
    self.results += [text]
def flush(self):
    pass
def print_(self):
    for x in self.results: print(x)
def return_(self):
    return self.results
def clear_(self):
    self.results = []

when passed as

O = OUTPUT() # Necessarily to remember results, but see below.

help = pydoc.Helper(O)

will store all results in the OUTPUT instance. Of course, beginning with O = OUTPUT() is not the best idea (see below). render_doc is not the central output point; output is. I wanted OUTPUT so I could keep large outputs from disappearing from the screen using something like Mark Lutz' "More". A different OUTPUT would allow you to write to files.

You could also add a "return" to the end of the class pydoc.Helper to return the information you want. Something like:

if self.output_: return self.output_

should work, or

if self.output_: return self.output.return_()

All of this is possible because pydoc is well-designed. It is hidden because the definition of help leaves out the input and output arguments.

Answer 5

Selected answer didn't work for me, so I did a little more searching and found something that worked on Daniweb. Credit goes to vegaseat. https://www.daniweb.com/programming/software-development/threads/20774/starting-python/8#post1306519

# simplified version of sending help() output to a file
import sys
# save present stdout
out = sys.stdout
fname = "help_print7.txt"
# set stdout to file handle
sys.stdout = open(fname, "w")
# run your help code
# its console output goes to the file now
help("print")
sys.stdout.close()
# reset stdout
sys.stdout = out

Answer 6

To get a "clean" text output, just as the built-in help() would deliver, and suitable for exporting to a file or anything else, you can use the following:

>>> import pydoc
>>> pydoc.render_doc(len, renderer=pydoc.plaintext)
'Python Library Documentation: built-in function len in module builtins\n\nlen(obj, /)\n    Return the number of items in a container.\n'