[Edu-sig] The fate of raw_input() in Python 3000

[Brian Blais]

Andre Roberge wrote:
 > The following is something I have been pondering for quite a while now
 > and am wondering what other people on this list think.
 >
 > According to PEP 3100
 > (http://www.python.org/dev/peps/pep-3100/ )
 > raw_input()  [as well as input()] is recommended for removal from the
 > built-in namespace, to be replaced by sys.stdin.readline().
 >
 > While I don't think anyone can argue that this removal makes a major
 > difference for Python as a programming language, I believe it makes a
 > significant difference for using Python as a learning language, adding
 > a non-trivial barrier to learning.
 >
 > Consider the following fake sessions at the interpreter prompt, where
 > I use extra parentheses to turn print as a function (as is also
 > proposed in Python 3000) - these parentheses can of course be used
 > with today's Python.
 >
 > # First ever program
 >>>> print("Hello world!")
 > Hello world!
 >
 > # More complicated example from the first interactive session using
 > today's version
 >>>> name = raw_input("Enter your name: ")
 > Enter your name: Andre
 >>>> print("Hello " + name + "!")
 > Hello Andre!
 >
 > # More or less the same example using the proposed changes.
 >>>> import sys
 >>>> print("Enter your name: ")
 > Enter your name:
 >>>> name = sys.stdin.readline()
 > <-- Andre
 >>>> print("Hello " + name + "!")
 > Hello Andre!
 >
 > To explain the above *simple* program to a beginner, we'd need:
 > 1. to introduce the import statement
 > 2. to introduce the dot notation (something Kirby would be happy with ;-)
 >
 > Furthermore, the flow is not the same as with today's raw_input().
 >
 > I don't like it.
 >
 > While I totally agree with the proposed removal of input()  [anything
 > using eval() in a hidden way is *bad*], my preference would be to keep
 > raw_input()'s functionality, perhaps renaming it to user_input() or
 > ask_user().
 >
 > Thoughts?
 >

I think that both should stay, perhaps with different names as suggested by others. 
It would seem that eval(stdin.readline()) is far more confusing to beginners.  I 
don't see input() as dangerous at all, because no serious developer is going to 
include it in an end-product, and a beginner would never be in a position to do any 
real harm.  On the other hand, input() is extremely useful, and concise.

So, is this removal a done-deal, or is there some effective way of reversing the 
decision?  Does Guido read this list?


             bb



-- 
-----------------

              bblais at bryant.edu
              http://web.bryant.edu/~bblais