Python: apply lower() strip() and split() in one line

Question

In python, what's the fastest way to define variables from splitting a string, but also converting to lowercase and striping white spaces?

Some thing like

args.where = 'Sn = Smith'
a,v = args.where.lower().split('=').strip()

Answer 1

You are splitting a string into a list, and you can't strip the list. You need to process each element from the split:

a, v = (a.strip() for a in args.where.lower().split('='))

This uses a generator expression to process each element, so no intermediary list is created for the stripped strings. Python will throw an exception here if the expression doesn't produce exactly two values.

To focus on speed in this case is.. pointless, unless you are doing this on a very large body of elements. You can micro-optimise the above with map(), though:

a, v = map(str.strip, args.where.lower().split('='))

but the cost in readability may just not be worth it, not for just 2 elements.