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Python 3.2 has some deadly infection


On Thu, Jun 5, 2014 at 6:05 PM, Marko Rauhamaa <marko at pacujo.net> wrote:
> Chris Angelico <rosuav at gmail.com>:
>
>> If, in Python, I say print("Hello, world!"), I expect that to produce
>> a line of text on the screen, without my code having to encode that to
>> bytes, figure out what sort of newline to add, etc, etc.
>
> That example in no way represents the typical Python program (if there
> is one).

It's simpler than most, but use of print() is certainly quite common.
A naive search of .py files in my /usr came up with five thousand
instances of ' print(', and given that that search won't necessarily
find a Python 2 print statement (and I'm on Debian Wheezy, so Py2 is
the system Python), I think that's a fairly respectable figure.

>> Only an extreme few Unix programs actually manipulate binary standard
>> streams
>
> That's quite an assumption to make.

Okay. Start listing some. You have (de)compression programs like gzip,
which primarily work with files but can work with standard streams;
some image or movie manipulation programs (eg avconv) can also read
from stdin, although again, it's far more common to use files; cat
will happily transmit binary untouched, but all its options (at least
the ones I can see in my 'man cat') are for working with text.

What else do you have? Let's see... grep, sort, less/more, sed, awk,
these are all text manipulation programs. All your "give me info about
the system" programs (ls, mount, pwd, hostname, date.......) print
text to stdout. Some also read from stdin, like md5sum and related.

Piles and piles of programs that work with text. A small handful that
work with binary, and most of them are more commonly used directly
with files, not with pipes. The most common case is that it all be
text.

>> we should have print() and input() "naturally just work" with Unicode
>
> No problem there. I couldn't imagine using either function for anything
> serious.

I don't know about those exact functions, but I do know that there are
plenty of Python programs that use the console (take hg as one fairly
hefty example). Maybe input() isn't all that heavily used, but
certainly print() is a fine function. I can not only imagine using
them seriously, I *have used* them, and their equivalents in other
languages, seriously.

If the standard streams are so crucial, why are their most obvious
interfaces insignificant to you?

ChrisA