[Tutor] creating files with python and a thanks

[Erik Price]

On Saturday, February 16, 2002, at 09:37  AM, Sheila King wrote:

> f = open(r'c:\windows\temp\myfile.mbg', 'w')
> f.write('this is my file\nmy stuff\nis in\nmy\nfile')
> f.close()
>
> (I used the r in front of the quotes, so that it will interpret the
> string as a "raw" string, and not assume the \t on \temp represents the
> escape sequence for a tab character.)

A quick question on this 'r' flag:

I use a unix-style filesystem, so I wouldn't have the same problem as 
above (it would be './temp/myfile.mbg', and I'm making the assumption 
that /t has no special meaning, though it might).  But is it generally 
good practice to use the 'r' flag like this when you have no intention 
of using variable/shell expansion?

In PHP, as well as Bash programming, single quotes are used for when you 
wish this effect -- a 'literal' string.  But double-quotes are used when 
you are okay with \t matching [tab] and other meta-characters.  Judging 
from this example, the Python equivalent is using 'open(r'string', 'w')'.

Do you try to always use the 'r' option -except- when you want 
expansion, or is the general practice to only use it when you -need- it 
to prevent a metacharacter like \t from being expanded?

Thank you,


Erik