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From: Peter Otten <__peter__@web.de>
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Subject: Re: avoid for loop calling Generator function
Date: Mon, 22 Feb 2016 14:34:08 +0100
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Xref: csiph.com comp.lang.python:103341

Arshpreet Singh wrote:

> Hi, I am converting PDF into text file, I am using following code.
> 
> from pypdf2 import PdfFileReader
> 
> def read_pdf(pdfFileName):
> 
>     pdf = PdfFileReader(pdfFileName)
> 
>     yield from (pg.extractText() for pg in pdf.pages)
> 
> for i in read_pdf('book.pdf'):
>      print(i)
> 
> I want to avoid for loop , I also tried to create another function and
> call read_pdf() inside that new function using yield from but I think I am
> missing real picture here

While it is possible to replace the loop with

next(filter(print, read_pdf("book.pdf")), None)

or the slightly less convoluted

sys.stdout.writelines(map("{}\n".format, read_pdf("book.pdf")))

the for loop is the obvious and therefore recommended solution. Personally, 
I would also replace

>     yield from (pg.extractText() for pg in pdf.pages)

with the good old

for pg in pdf.pages:
    yield pg.extractText()

and reserve the generator expression for occasions where it has a 
demonstrable advantage in readability.