Write and read objects from files .

[Chris Barker]

> > I'm a python beginner and looking for :
> > 1. A way to save a list on a file (as a string) and then retrieve it
> > back (read the string from the file and build automatically a list) .

you might want to try repr() and eval(). In general, the goal of repr()
is to produce a string such that:

eval(repr(x)) = x

so you can do:

file.write(repr(YourList))

and later:

eval(file.read())

You'r reading code will probably be a lot more complex, if you have more
than one item stored in the file, but this should give you the idea.

Here is a short example at the command line:

>>> l1 = ['this', 'that', '56']
>>> l1
['this', 'that', '56']
>>> s = repr(l1)
>>> s
"['this', 'that', '56']"
>>> l2 = eval(s)
>>> l2
['this', 'that', '56']
>>> l2 == l1
1
>>>

-Chris



-- 
Christopher Barker,
Ph.D.                                                           
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