Mutable strings - symetry with list types

[Gordon Airport]

Dennis Lee Bieber wrote:

> Prior to the creation of string methods, you'd have done
> 
> import string
> 
> ...   string.join(blah, ' ')
> 
> 

Yes, it looks even worse that way. I guess that it's just rare to use a 
literal in the code as an object...I'm having trouble thinking of other 
situations where you use the ability, but I won't pretend to be an 
expert in the language.

>>not obvious and it looks like a hack, IMO. Plus you can't do
>>somestring = '%s %s %s' % [ 'nine', 'bladed', 'sword' ]
> 
> 
>         If you know both sides have equal numbers of terms (the %s matches the 
> number of entries in the list) you /can/ do a minor modification to 
> that line:
> 
> somestring = "%s %s %s" % tuple(["nine", "bladed", "sword"])

I just found it strange that you couldn't do it directly without 
'casting'...Probably doesn't come up much anyway. Now that I think about 
it it's an assignment so it's not really relevant to the discussion of 
mutable strings.

> 
>         Of course, you could also create a dictionary and store those as 
> attributes (though to my mind, you have a sword with one modifier 
> "nine-bladed"; as is it could be interpreted to mean nine 
> bladed-sword(s) -- though all swords are bladed...).
> 
> 
>>>>weapon = {"type":"Sword", "attribute":"bladed", "modifier":"nine"}
>>>>weapon
> 
> {'attribute': 'bladed', 'modifier': 'nine', 'type': 'Sword'}
> 
>>>>somestring = "%(modifier)s %(attribute)s %(type)s" % weapon
>>>>somestring
> 
> 'nine bladed Sword'
> 

All very handy, but I don't see how it could be done better with mutable 
strings. I need to come up with some examples of applications.