[Python-Dev] Replacement for print in Python 3.0

Bill Janssen janssen at parc.com
Thu Sep 1 21:03:23 CEST 2005

I have to agree with Barry, Paul, Fredrik, Reinhold, etc.  Removing
the "print" statement would immediately break at a fundamental level
15 years of tutorials, books, and examples, many of which start with

>>> print "Hello, World!"

Of course, maybe that's the idea -- this is not your father's Python!
(Though that slogan apparently didn't work out so well for

Is there a syntax trick here?  Suppose start-of-the-line function
names not followed by an open-paren, but followed by comma-separated
lists of expressions, were treated as if the rest of the line were
arguments to a function.  That is, suppose

  print "foo", 3, dir(sys)

was automagically converted to

  print ("foo", 3, dir(sys))

Not sure I like this kind of trickyness, though.  Though it might be
useful for "assert", "raise", maybe "exec", too.

I also don't quite see the point of adding new top-level reserved
words or built-in functions like "write".  It clutters the namespace
without being much of an improvement over "sys.stdout.write", IMO.
Some kind of printf would be nice to have, but with Python's forgiving
syntax is easy enough to add yourself.

> Maybe the syntax used in the string.Template class is the way to go?

If you'd consider extending the Template syntax to positional
parameters ($1, $2, etc.), then perhaps "print" could be modified to
use the template for formatting, if it occurs as the first argument:

  print string.Template("arg $1, arg $2"), arg1, arg2

with an alternate form

  printf "arg $1, arg $2", arg1, arg2

where the first arg is required to be a template pattern string.  This
is a nice improvement over C printf in that you can re-use arguments.

What happens to Template() when the string module goes away?  Do we
write "arg $1, arg $2".Template() instead?


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