Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]


Groups > comp.lang.python > #19653

Re: except clause syntax question

Date 2012-01-31 08:56 -0800
From Ethan Furman <ethan@stoneleaf.us>
Subject Re: except clause syntax question
References <mailman.5218.1327946109.27778.python-list@python.org> <4f272f1f$0$29989$c3e8da3$5496439d@news.astraweb.com> <mailman.5243.1328018257.27778.python-list@python.org> <4f27ffd8$0$29989$c3e8da3$5496439d@news.astraweb.com> <440642C3-B9CD-4BC7-AF57-4013238C2C5C@declareSub.com>
Newsgroups comp.lang.python
Message-ID <mailman.5256.1328032352.27778.python-list@python.org> (permalink)

Show all headers | View raw


Charles Yeomans wrote:
> On Jan 31, 2012, at 9:51 AM, Steven D'Aprano wrote:
>> On Tue, 31 Jan 2012 08:57:31 -0500, Charles Yeomans wrote:
>>
>>> I don't think of a tuple as a container, and I don't think it a
>>> misunderstanding on my part to think this.
 >>
>> Well, it is a misunderstanding, because tuples ARE containers. You
 >> might as well say "I don't think of boxes as containers". What
 >> exactly are they if not containers?
> 
> Tuple is a heterogenous datatype that allows one to define objects
 > ad hoc.

And any object can be seen as a container for its component pieces -- 
some are just more general than others.

Compare:

location = (13, 4, 9)            # line, word, char
time = (10, 15, 41)              # hour, minute, second
result = ('this', 'that', 'huh') # result a, result b, result c

with:

record1 = Record('Ethan', 41, Male)
record2 = Record('Charles', 37, Male)
record3 = Record('Steven', 43, Male)
record4 = Record('Jennifer', 39, Female)

In this example, Records have a set layout and so it is more common to 
think of a Record as a thing;  location, time, and result, however, are 
all random tuples created on the fly with no absolute restrictions on 
what goes in which position.

lists, dicts, sets, and tuples are general purpose containers; strs (and 
most user defined classes) are special purpose containers.

> That is to say, a tuple represents a single thing distinct from its
 > components.

You could say that about a list as well.  Doesn't change the fact that a 
list is a container.

> One can certainly view a tuple as a list, just as one can view a string
 > as a list of characters, and sometimes that's useful; the Python dictum
 > "there should only be one way to do it" doesn't imply that there is only
 > one way to think of it.

The 'dictum' is "there should only be one *obvious* way to do it" 
(emphasis added).

~Ethan~

Back to comp.lang.python | Previous | NextPrevious in thread | Next in thread | Find similar | Unroll thread


Thread

except clause syntax question Charles Yeomans <charles@declareSub.com> - 2012-01-30 12:41 -0500
  Re: except clause syntax question Mel Wilson <mwilson@the-wire.com> - 2012-01-30 14:15 -0500
  Re: except clause syntax question Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2012-01-31 00:00 +0000
    Re: except clause syntax question Devin Jeanpierre <jeanpierreda@gmail.com> - 2012-01-30 19:25 -0500
    Re: except clause syntax question Charles Yeomans <charles@declareSub.com> - 2012-01-31 08:57 -0500
      Re: except clause syntax question Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2012-01-31 14:51 +0000
        Re: except clause syntax question Charles Yeomans <charles@declareSub.com> - 2012-01-31 11:23 -0500
        Re: except clause syntax question Devin Jeanpierre <jeanpierreda@gmail.com> - 2012-01-31 11:38 -0500
        Re: except clause syntax question Charles Yeomans <charles@declaresub.com> - 2012-01-31 12:29 -0500
        Re: except clause syntax question Ethan Furman <ethan@stoneleaf.us> - 2012-01-31 08:56 -0800
    Re: except clause syntax question Terry Reedy <tjreedy@udel.edu> - 2012-01-31 19:12 -0500
    Re: except clause syntax question Charles Yeomans <charles@declareSub.com> - 2012-01-31 19:27 -0500
  Re: except clause syntax question Mel Wilson <mwilson@the-wire.com> - 2012-01-31 08:24 -0500
    Re: except clause syntax question Charles Yeomans <charles@declareSub.com> - 2012-01-31 13:04 -0500
  Re: except clause syntax question Duncan Booth <duncan.booth@invalid.invalid> - 2012-01-31 22:03 +0000
    Re: except clause syntax question Chris Angelico <rosuav@gmail.com> - 2012-02-01 11:53 +1100
      Re: except clause syntax question Mel Wilson <mwilson@the-wire.com> - 2012-01-31 23:39 -0500
    Re: except clause syntax question Ian Kelly <ian.g.kelly@gmail.com> - 2012-01-31 18:09 -0700
    Re: except clause syntax question Ian Kelly <ian.g.kelly@gmail.com> - 2012-01-31 18:12 -0700
    Re: except clause syntax question Chris Angelico <rosuav@gmail.com> - 2012-02-01 13:46 +1100

csiph-web