元组索引和打印

Question

Python beginner here and a little confused with tuples when working with them as lists. I have the code below and to my understanding the peek function should return the first tuple pair but in reality it returns only the first word of that pair. Why is this??

Thanks in advance everyone.

tuples = [('big', 'apple'), ('small', 'orange'), ('medium', 'berry')]

def peek(word_list):
    if word_list:
        word = word_list[0]
        return word[0]
    else:
        return None




peek(tuples) #prints big

print tuples[0] #prints ('big', 'apple')

Answer 1

word = word_list[0]      # first tuple
print word[0]            # first entry of the first tuple

You've got two [0] dereferences. This code is equivalent to

print word_list[0][0]    # first entry of the first tuple

Get rid of one of them.

word = word_list[0]      # first tuple
print word               # first tuple

Answer 2

Try this out and see:

word_list = [('big', 'apple'), ('small', 'orange'), ('medium', 'berry')]
word = word_list[0]
print(word)
print(word[0])

Answer 3

In peek function, replace

print word[0]

with

print word

Since word[0] is actually word_list[0][0] which is 1st element in 1st tuple, ie "big". In short, think of "tuples" as a 2*3 array.