String adding.

[Huaiyu Zhu]

On Wed, 18 Oct 2000 11:03:11 +0100, Jon Ribbens
<jon+python-list at unequivocal.co.uk> wrote: 
>Alex Martelli <aleaxit at yahoo.com> wrote:
>> > BTW `x` is the same as repr(x)
>> 
>> Exactly because of this, I would suggest
>>     "<%s>" % whatever
>> as a preferable solution to
>>     '<' + `whatever` + '>'
>
>Yes, this is one of the things that confuses me in Python. I can't see
>repr ever being used in real programs. Why is there a syntactic shortcut
>for it? Surely 'str' is almost always what you actually want?

repr is suppose to contain information to reconstruct the object.
For example

>>> from Numeric import *
>>> a = arange(5)
>>> a
array([0, 1, 2, 3, 4])
>>> print a
[0 1 2 3 4]

Say if you want to write something onto a text file and later eval it back,
you would want to use repr.

>>> b = `a`
>>> b
'array([0, 1, 2, 3, 4])'
>>> eval(b)
array([0, 1, 2, 3, 4])
>>> print eval(b)
[0 1 2 3 4]

Huaiyu