What is not objects in Python?

[Gabriel Genellina]

Re: What is not objects in Python?

En Tue, 30 Sep 2008 08:07:18 -0300, Steve Holden <steve@holdenwe b.com>
escribió:

Terry Reedy wrote:

>Steven D'Aprano wrote:

>>Arghh! No!!! |x| should be abs(x), not len(x). Just ask mathematicians
>>and physicists.

>>
>It should be both, just as + is addition for numbers and concatenation
>for sequences. Or we could have just one built-in -- size() instead of
>abs() and len(). For non-sequence collections, size() would be better
>than len() anyway.
>>

And how are these "non-sequence collections" to be distinguished? And
how does size() differ from len() in that case?

Consider a tree, or a graph. The number of elements they have is not
naturally described as their "length", the usual term is "size" instead.
"Length" is adequate for one-dimensional structures only; even len(dict)
is a bit controversial.
Had Python used the more generic size and __size__ from the beginning,
we'd be all happy now :) But it's too late to change things.

--
Gabriel Genellina

[Aaron \Castironpi\ Brady]

Re: What is not objects in Python?

On Sep 30, 7:39 am, Steve Holden <st...@holdenwe b.comwrote:

Steven D'Aprano wrote:

On Mon, 29 Sep 2008 21:03:07 -0700, namekuseijin wrote:

>

>Why isn't len implemented as a str.len and list.len method instead ofa
>len(list) function?
Because postfix notation sucks.  The natural way of spelling is
adjective+noun and verb+predicate.

>

"Natural"?

>

You mean phrases like "heir apparent" and "worst choice imaginable" are
unnatural?

>
They are certainly far from normal usage, as my dog yellow would be
certain to agree.
>

To say nothing of languages like Spanish, Albanian, Italian,
Cornish, Vietnamese, Hebrew...

>
It's long been a convention in the Western programming world to pretend
no other language than English and no other codes than ASCII exist.
>
The fact that Python is beginning to come to terms with Unicode is a
tribute to certain developers' persistence.
>
regards
 Steve
--
Steve Holden        +1 571 484 6266   +1 800 494 3119
Holden Web LLC              http://www.holdenweb.com/

How do you have a yellow dog, and what does s/he know about natural
noun-verb usage?

[Boris Borcic]

Re: What is not objects in Python?

42, for instance.

Proof :

>>42 is not object

True

QED

[William McBrine]

Re: What is not objects in Python?

On Wed, 01 Oct 2008 17:56:34 +0200, Boris Borcic wrote:

42, for instance.
>
Proof :
>

>>42 is not object

True
>
QED

>>isinstance(42 , object)

True

--
09 F9 11 02 9D 74 E3 5B D8 41 56 C5 63 56 88 C0 -- pass it on

[greg]

Re: What is not objects in Python?

Gabriel Genellina wrote:

Had Python used the more generic size and __size__ from the beginning,
we'd be all happy now :)

Not necessarily -- len is slightly shorter, and more
comfortable to type on a qwerty keyboard.

But in any case, size-likers have an easy solution:

size = len

:-)

(BTW, try doing that with the x.len() notation!)

--
Greg


But it's too late to change things.

>

[greg]

Re: What is not objects in Python?

Aaron "Castironpi " Brady wrote:

How do you have a yellow dog,

It's not a yellow dog, it's a dog yellow. Attention pay! :-)

--
Ewing Gregory

[Marc 'BlackJack' Rintsch]

Re: What is not objects in Python?

On Fri, 03 Oct 2008 19:10:27 +1200, greg wrote:

But in any case, size-likers have an easy solution:
>
size = len
>
:-)
>
(BTW, try doing that with the x.len() notation!)

def size(obj):
return obj.len()

or

size = operator.method caller('len')

in Python 2.6 and up.

:-)

Ciao,
Marc 'BlackJack' Rintsch

[Bruno Desthuilliers]

Re: What is not objects in Python?

Boris Borcic a écrit :

42, for instance.
>
Proof :
>

>>42 is not object

True
>
QED
>

Lol.

[Tim Rowe]

Re: What is not objects in Python?

2008/9/30 Lie Ryan <lie.1296@gmail .com>:

Actually str.len and len(str) is just like saying "the string's length"
and "the length of the string". There is no difference between the two
except for personal preference. (I am no linguist-- not even a native
speaker of English --but I think there is a subtle difference on
emphasis, "the string's length" emphasizes on the length being string's
property, while "the length of the string" emphasizes on the length
itself, am I correct?)

Well, I'm doing a linguistics degree, so I'm not a linguist /yet/, but
I think I know this one. There is the difference in emphasis that you
mention, but there may be something more significant. In both forms,
"length" is what linguists call the "head" of the noun phrase: it's
the actual thing being talked about. In "The string's length" the
head is only pre-modified ("the string's" comes before the head and
there's nothing after the head). "The length of the string" has both
pre- and post- modification ("The" before, "of the string" after).
Post modification in noun phrases has been measured to be much less
frequent in spoken English than in written English, and it gets
progressively more common as the writing style gets more formal. That
suggests that "the string's length" is an easier phrase to produce and
understand, but "the length of the string" sounds more official.

--
Tim Rowe

[Aaron \Castironpi\ Brady]

Re: What is not objects in Python?

On Oct 3, 5:10 am, "Tim Rowe" <digi...@gmail. comwrote:

2008/9/30 Lie Ryan <lie.1...@gmail .com>:
>

Actually str.len and len(str) is just like saying "the string's length"
and "the length of the string". There is no difference between the two
except for personal preference. (I am no linguist-- not even a native
speaker of English --but I think there is a subtle difference on
emphasis, "the string's length" emphasizes on the length being string's
property, while "the length of the string" emphasizes on the length
itself, am I correct?)

>
Well, I'm doing a linguistics degree, so I'm not a linguist /yet/, but
I think I know this one. There is the difference in emphasis that you
mention, but there may be something more significant. In both forms,
"length" is what linguists call the "head" of the noun phrase: it's
the actual thing being talked about.  In "The string's length" the
head is only pre-modified ("the string's" comes before the head and
there's nothing after the head). "The length of the string" has both
pre- and post- modification ("The" before, "of the string" after).
Post modification in noun phrases has been measured to be much less
frequent in spoken English than in written English, and it gets
progressively more common as the writing style gets more formal.  That
suggests that "the string's length" is an easier phrase to produce and
understand, but "the length of the string" sounds more official.
>
--
Tim Rowe

.... Unless, there is some corresponding distinction in mechanics
between speaking and writing. That is, if something about the process
of generating writing makes it, post-modification, easier. I'm going
to assume that it's been observed across all modes of writing too, (in
addition to across all formality levels), where in all cases it was
equally easy to go back and edit, which is impossible in speech. And,
in the cases where the entire process of writing was observed, that
neither kind of modification occurred more frequently in revisions.

[Tim Rowe]

Re: What is not objects in Python?

... Unless, there is some corresponding distinction in mechanics

between speaking and writing. That is, if something about the process
of generating writing makes it, post-modification, easier. I'm going
to assume that it's been observed across all modes of writing too, (in
addition to across all formality levels), where in all cases it was
equally easy to go back and edit, which is impossible in speech. And,
in the cases where the entire process of writing was observed, that
neither kind of modification occurred more frequently in revisions.

There are such distinctions. In writing, more time is available to
produce the text, there is the opportunity to revise the text, the
reader has more time to read the text and the reader has the
opportunity to re-read the text. Unfortunately, because of the "more
time is available to produce the text", observing the writing process
would be of limited value.

I don't think it's that post-modification becomes easier than
pre-modification in writing, I think it's that post-modification
becomes more feasible in writing, and is preferred for stylistic
reasons.

When you say "across all modes of writing" I'm not sure what you mean
(linguistically , writing /is/ the mode!) -- I suspect you mean either
register (style of writing) or medium (loosely, method of writing).

[greg]

Re: What is not objects in Python?

Marc 'BlackJack' Rintsch wrote:

On Fri, 03 Oct 2008 19:10:27 +1200, greg wrote:

>>(BTW, try doing that with the x.len() notation!)

def size(obj):
return obj.len()
>
or
>
size = operator.method caller('len')

No, what I meant was that if the normal way of getting
the len of something were to write x.len() instead of
len(x), you wouldn't be able to globally substitute
that syntax with x.size().

--
Greg