[Tutor] help with exercise 15 of zed shaw's LPTHW

[Alan Gauld]

On 06/07/16 15:04, lohecn at tuta.io wrote:

> script, filename = argv
> txt = open (filename)
> 
> print "Here's your file %r: " % filename
> print txt.read()
> 
> print "Type the filename again: "
> file_again = raw_input("> ")
> 
> txt_again = open(file_again)
> print txt_again.read()


> why do I have to create a variable txt_again to assign it to the open 
> function and them print the file?

You don't, and could get away with a single
variable - filename. Like this:

filename = argv[1]
print "Here's your file %r: " % filename
print open(filename).read()

filename = raw_input("Type the filename again: >")
print open(filename).read()

But your book is (I assume) trying to teach you
good practice.

While you could have just printed the result of read directly,
its better not to over complicate code by doing too much in one
line (for a start, its harder to debug) the same variable.
Variables are cheap to create and if given useful names
tell us a lot about the purpose of the code.

In this case it's all a bit trivial, just printing the file
content, but if you were doing more complex processing
storing the file (and data) in variables would be the
best choice.

-- 
Alan G
Author of the Learn to Program web site
http://www.alan-g.me.uk/
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