Question

I’m doing some exploring of various languages I hadn’t used before, using a simple Perl script as a basis for what I want to accomplish. I have a couple of versions of something, and I’m curious which is the preferred method when using Python — or if neither is, what is?

Version 1:

workflowname = []
paramname = []
value = []
for line in lines:
        wfn, pn, v = line.split(",")
        workflowname.append(wfn)
        paramname.append(pn)
        value.append(v)

Version 2:

workflowname = []
paramname = []
value = []
i = 0;
for line in lines:
        workflowname.append("")
        paramname.append("")
        value.append("")
        workflowname[i], paramname[i], value[i] = line.split(",")
        i = i + 1

Personally, I prefer the second, but, as I said, I’m curious what someone who really knows Python would prefer.

Answer 1

Bogdan’s answer is best. In general, if you need a loop counter (which you don’t in this case), you should use enumerate instead of incrementing a counter:

for index, value in enumerate(lines):
    # do something with the value and the index