[docs] Bug:(

panax at zmail.lt panax at zmail.lt
Sat Mar 3 22:28:49 CET 2012

I have found an interesting thing. Let's compare two _very_ simple and  functionally identical scripts.
They both check one by one chars in the string s if they are alpha or no:
if s[0].isalpha():  print("0-yes")
else:  print("0-no")
if s[1].isalpha():  print("1-yes")
else:  print("1-no")
if s[2].isalpha():  print("2-yes")
else:  print("2-no")
if s[3].isalpha():  print("3-no")
else:  print("3-no")
if s[4].isalpha():  print("4-no")
else:  print("4-no")
if s[5].isalpha():  print("5-yes")
else:  print("5-no")
 - produces (Python 2.7.2, with my comments at the right):

aaaaaa   -the string
0-yes    -it's alpha ok
3-no     -!!!  this 'a' is not alpha!
4-no     -!!!  and this also... 
5-yes    - ok again

Look at pos.3 and 4, those chars now are NOT alpha!
On the other hand, functionally the same script, but with not direct (not by literal, but by variable j) char addressing, performs ok:
for j in range(len(s)):
  if s[j].isalpha():  print(s[j]+"- alpha")
  else:  print(s[j]+"- Not alpha")

Seems the behaviour doesn't depend on the string content, but rather on the position of char and the addressing way (literal or no).

Would be glad to be helpful...
I use Python 2.7.2 (last),  WinXp as a host. 
One more mention - these scripts were running from files, not as dialog session.
Sorry, if this is known bug, now have no time to check through.
And don't tell me this is a feature!

Yours notes are welcome!

God bless the Py!

panax at zmail.lt

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