n = lambda x: print x
mwh21 at cam.ac.uk
Thu May 4 09:52:29 EDT 2000
"Warren Postma" <embed at geocities.com> writes:
> In a moment of perverse glee, I decided to type the statement in to see what
> it does. The question I wondered was, if Python accepted this:
> n = lambda x: print x
> What would it do with this:
> n = (lambda x: print x,y)
> Is the comma part of the print statement, or would n become a tuple of two
> values? :-)
> Is the first construct s pecifically disallowed in the python grammar
> somehow? print is a bit of a weirdball function in that it is invoked
> without parenthesis. (The most BASIC-like feature of Python).
It's not a function, it's a statement (like exec, though that was once
a function). And you can't have statements in lambda expressions.
FWIW, "lambda" binds tighter than ",":
>>> lambda x:1,1
(<function <lambda> at 812a220>, 1)
> Could we in fact say that if fewer exceptions to rules makes a language
> simpler then the PRINT statement is a bad idea and a PRINT( x,y,z) function
> would have been a much better idea?
I mean, just take a look at Joe Strout's brilliant little "python
for beginners" page. Replace all print-statements with
sys.stdout.write( string.join(map(str, args)) + "\n") and you'll
surely won't get any new beginners. And That Would Be A Very Bad
Fredrik Lundh, 27 Aug 1996
I.e. print is a convenience. Python generally emphasises consistency
over convenience, but in this case, the convenience functionality is
so convenient it has been included.
> Why did Guido not parenthesize arguments to PRINT when designing Python?
Maybe so you can do
>>> print 1,
? I don't really know.
> Look, a Syn! Otherwise, this language is perfect.
No, it isn't; but there's another quote about Python that I like very
much (I have lots of these):
Python is a language that gets its compromises exactly right.
I think that on was Don Beaudry, but I'm not sure.
I'd like multimethods, myself.
> ;-) I love Python.
So do I.
I saw `cout' being shifted "Hello world" times to the left and
stopped right there.
-- Steve Gonedes
More information about the Python-list