Python parser script layout

Question

Hi everyone!

I'm writing a simple Python parser, where I loop over each line in a file, and prosess it further if the right conditions are met. My short start:

    def identify(hh_line):
        if(re.match(regex.new_round, hh_line)):
            m = re.match(regex.new_round, hh_line)
            # insert into psql

        ...

        if(re.match...

..and I was wondering what's the best way (practice) to approach this task, since this is the first time I write Python.

Thanks! =)

Answer 1

First of all, it's redundant to run the match twice - instead, run it, store the result, and branch off of that:

m = re.match(regex.new_round, hh_line)
if m:
    # ...

Next, if you have a bunch of regex -> processing combinations, you might instead make a dict of regex -> function mappings, and then just iterate over it:

def process_a(data):
    # ...

def process_b(data):
    # ...

regex_to_process = {
    'regex_a': process_a,
    'regex_b': process_b,
}

for hh_line in <file object>:
    for regex,process in regex_to_process.iteritems():
        m = re.match(regex, hh_line)
        if m:
            process(hh_line)