Question

Hi,

I'm working on pset 5 doing the ghost game. I do not understand why the pg does not halt when the player fails (second if and first elif statement below). Instead it keeps asking for a new letter. What am I doing wrong?

main loop for ghost game
def play_ghost(player,word):
go = 'y'
while go == 'y':
letter = raw_input('Please enter a letter >> ')
if letter not in string.ascii_letters:
print 'Not a valid letter.'
else:
print player+' says letter '+letter
word = word+letter
# if fgt is word of more than 3 letters, failure
if len(word) > 3 and word in wordlist:
print '%s loses because %s is a word!\n'%(player,word)
go = 'no'
# if fgt does not start a word failure
elif not prefix(word,wordlist):
print '%s loses because no word starts with %s!\n'%(player,word)
go = 'no'
# else switch player
else:
new_player = switch[player]
print '\nCurrent word fragment is %s'%(word)
print "%s's turn"%(new_player)
play_ghost(new_player,word)
print "Good bye!"

Answer 1

please use a code pasting site to post your code
dpaste.com
pastebin.com
codepad.org
.....

Answer 2

Ok so here is the link

http://dpaste.com/hold/750836/

and my question again: why does the pg not halt when the player fails (second if and first elif statement below). Instead it keeps asking for a new letter.

Answer 3

It is because this is a recursive function. Since play_ghost() calls itself in the second else statement, even if that call ends in a failure, the while loop in the current play_ghost() call won't end because your value of go is still 'y'.

My suggestion: remove the while loop because your recursive function already does the looping.

Answer 4

Yes of course. Thanks a lot. Here is the revised code

http://dpaste.com/751020/

Answer 5

maybe the function should return for every conditional that results in a player loosing.

please post your prefix function, I'd like to see it.

Answer 6

Does it work now?

Answer 7

Yes thanks it works. Here is the prefix function

http://dpaste.com/751267/