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Python's print statement was surface-level beautiful, with subsurface flaws:

1) it modified the file object's "softspace"

  >>> class MyFile(object):
  ...   softspace = "Hello"
  ...   def write(self, s):
  ...     pass
  ...
  >>> f = MyFile()
  >>> f.softspace
  'Hello'
  >>> print >>f, "spam"
  >>> f.softspace
  0
2) This wasn't a problem until >> was added, because of problem #2 - the print statement didn't originally let you print to anything other than stdout. Which meant that if you wanted to support writing to a file instead of a stdout then you had to re-implement print yourself.

In practice, I've also found that having print as a function adds functionality because I can do things like:

    print(*data_values, sep="\n")
which is a quick way to print each value in a list on its own line.


    for v in data_values: print v
Is exactly the same length but much more readable.


"Readable" is in the eye of the beholder, which is why I commented that this was something I personally found useful, rather than one of the two subtle flaws I mentioned.

I can also disable all print statements with "def print(* args, * * kwargs): pass" at the top of the module.

I've had times where I couldn't figure out where a print was coming from, so I could replace print() to check the arguments passed in:

   import builtins
   builtin_print = builtins.print

   def my_print(*args, **kwargs):
      if "looking for" in args: # adjust as appropriate
         1/0
      return builtin_print(*args, **kwargs)

   builtins.print = my_print
Previously I had to do that by wrapping sys.stdout with my own file-like object, to intercept write(). (Granted, not hard, but harder.)


The fact that you can overwrite built-in functions is not a point in favor of the language. Imagine you do this in a library and everyone using print() in their project would use a modified print instead. You could've just modified sys.stdout instead.


Sure, but I never said I was doing this in library code. I mentioned I was using it to track down an unexpected print statement.

And the other example was in module scope.




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