Ok, so in Python, arguments are evaluated first, left to right ! The outer-most function used in your sample is : file.write(self, filename, mode)
So the first argument evaluated is "self" ... and in your case "self" is "open(item, 'w')" so the first thing your line does is opening for writing the file named by "item" and as "w" empty the file ... you can read it afterward, it will be empty !
Pierre
PS: general in programs: do NEVER rely on arguments evaluation order, unless you have no other choices and you are damn sure of what you're doing. In any case, do NEVER do that if you're no expert in the programming language used.
Chad Crabtree a écrit :
I've tried this and I cannot figure out why this does not work. I figure this has something to do with order of operations. I figured someone would know exactly why it doesn't work. Wouldn't this start inside parens then from left to right?
open(item,'w').write(open(item,'r').read().replace(' ',''))
I tried this on the shell just trying to do some quick text
replacement because I could figure out how to get awk to do it, and I didn't want
to spend 5 hours RTFM. I got it to work by breaking it up to several statements, but I would like to know.
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