Qfyilyi

I'm parsing JSON objects and found this sample line of code which I kind of understand but would appreciate a more detailed explanation of:

for record in [x for x in records.split("n") if x.strip() != '']:

I know it is spliting records to get individual records by the new line character however I was wondering why it looks so complicated? is it a case that we can't have something like this:

for record in records.split("n") if x.strip() != '']:

So what do the brackets do ? and why do we have x twice in x for x in records.split....

Thanks

The "brackets" in your example constructs a new list from an old one, this is called list comprehension.

The basic idea with [f(x) for x in xs if condition] is:

def list_comprehension(xs):

    result = 

    for x in xs:

        if condition:

            result.append(f(x))

    return result

The f(x) can be any expression, containing x or not.

That's a list comprehension, a neat way of creating lists with certain conditions on the fly.

You can make it a short form of this:

a = 

for record in records.split("n"):

    if record.strip() != '':

        a.append(record)



for record in a:

    # do something

The square brackets ( ) usually signal a list in Python.