Python Forum

which is "better"?

    if opt[0].lower()=='-n':
        ...

or:

    if opt[0] in ('-n','-N'):
        ...

?

I like first one. However, I would use argparse.

how do you know my use case fits argparse?  or is it that you know that all your future use caes will?

you always could look at bytecode to see which one you like

import dis

def lower(a):
    a.lower() == 'a'
    
def isin(a):
    a in ['a', 'A']
    
dis.dis(lower)

print()

dis.dis(isin)

---

output

Quote:  4           0 LOAD_FAST                0 (a)
              2 LOAD_ATTR                0 (lower)
              4 CALL_FUNCTION            0
              6 LOAD_CONST               1 ('a')
              8 COMPARE_OP               2 (==)
             10 POP_TOP
             12 LOAD_CONST               0 (None)
             14 RETURN_VALUE

  7           0 LOAD_FAST                0 (a)
              2 LOAD_CONST               3 (('a', 'A'))
              4 COMPARE_OP               6 (in)
              6 POP_TOP
              8 LOAD_CONST               0 (None)
             10 RETURN_VALUE