On 25/05/2013 19:56, Jim Mooney wrote:
I thought tuples were immutable but it seems you can swap them, so I'm
confused:
a,b = 5,8
You've defined two names a and b so where's the tuple?
print a # result 5
a,b = b,a
You've redefined two names a and b to take the values that were held in
b and a so still no tuple.
print a # result 8, so they swapped
# but if I test the type of a,b I get a tuple
testit = a,b
Finally a tuple.
print type(testit) #comes out as a tuple
print testit, # result is (8,5)
# So how am I swapping elements of a tuple when a tuple is immutable?
#t rying so change a tuple since I just did it
testit[1] = 14 #program crashes - *TypeError: 'tuple' object does not
support item assignment *so the tuple I just changed is indeed immutable
Exactly as expected. So what precisely don't you understand?
--
Jim Mooney
"Coding? You can get a woman to do that!" he said with a sneer. --heard
from a physics professor in 1969
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Mark Lawrence
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