[Chicago] Making a list of strings

Massimo Di Pierro mdipierro at cs.depaul.edu
Mon Oct 19 20:13:08 CEST 2009


because in

y = list().append(whatever)

you are bot storing the vaue returned by list() but the value returned  
by append and append does not return the list it acts on. append  
always returns None.

On Oct 19, 2009, at 1:08 PM, Phil Robare wrote:

> OK fellow pythonistas,  can anyone explain what is going on here?
>
> 	I'm using a recent, but not most recent, version of Python.
> Python 2.5.4 (r254:67916, Dec 23 2008, 15:10:54) [MSC v.1310 32 bit  
> (Intel)]
>
> 	I want a list with a string value in it.  I make a sample string to
> put in a list.
> In [1]: s='string'
>
> 	The obvious way gives me something different but expected
> In [2]: list(s)
> Out[2]: ['s', 't', 'r', 'i', 'n', 'g']
>
> 	So I try appending something to a newly created empty list
> In [3]: y=list().append(s)
>
> 	And I get a null value.  This is unexpected,
> In [4]: y
>
> 	since doing the steps independantly gives me what I want.
> In [5]: y=list()
> In [6]: y.append(s)
> In [7]: y
> Out[7]: ['string']
>
>
> I want to pass this as a parameter and it seems non-pythonic to have
> to create a variable and then pass it when all I want is a single use.
> Any ideas for a better work-around?
>
> Phil
> _______________________________________________
> Chicago mailing list
> Chicago at python.org
> http://mail.python.org/mailman/listinfo/chicago



More information about the Chicago mailing list