Iterate over list of tuples using a variable for the tail tuple

Question

How to iterate over [(1,2,3), (2,3,1), (1,1,1)] while splitting each tuple into a head and a tail? I am searching concise an pythonic way like this:

for h, *t in [(1,2,3), (2,3,1), (1,1,1)]:
    # where I want t to be a tuple consisting of the last two elements
    val = some_fun(h)
    another_fun(val, t)

The above doesn't work for python 2.7.

@dcg That won't work either. Python 2 doesn't support this kind of unpacking as far as I know. — iz_, Mar 29 '19 at 00:25
`The above doesn't work for python 2.7` WOW. Learned something new here. — FailSafe, Mar 29 '19 at 00:37

score 1 · Answer 1 · answered Mar 29 '19 at 00:23

1

You could use a map to and list slicing:

for h, t in map(lambda x: (x[0], x[1:]), [(1,2,3), (2,3,1), (1,1,1)]):
    print("h = %s, t=%s"%(h, t))
#h = 1, t=(2, 3)
#h = 2, t=(3, 1)
#h = 1, t=(1, 1)

answered Mar 29 '19 at 00:23

pault

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Iterate over list of tuples using a variable for the tail tuple

1 Answers1