Basic list question

[sanora600]

>>> mylist = ['apple', 'banana', 'cherry']
>>> mylist[1:2] = ['kiwi', 'mango'] ## this translate to mylist[1] = ['kiwi', 'mango'] , so does this means the list is apended to mylist and it should be somethign like this [['apple',[ 'kiwi', 'mango'],  'cherry'] but why it is the way it is i.e ['apple', 'kiwi', 'mango', 'cherry']
>>> print (mylist)
['apple', 'kiwi', 'mango', 'cherry']
>>> print (mylist[1:2])
['kiwi']
>>>

this translate to mylist[1] = ['kiwi', 'mango'] , so does this means the list is apended to mylist and it should be somethign like this [['apple',[ 'kiwi', 'mango'], 'cherry'] but why it is the way it is i.e ['apple', 'kiwi', 'mango', 'cherry']

[deanhystad]

mylist[1:2] = ['kiwi', 'mango'] replaces a slice of mylist with the values in ['kiwi', 'mango']
mylist[1] = ['kiwi', 'mango'] replaces an element in mylist with the list ['kiwi', 'mango']

Slices are interesting.

https://www.30secondsofcode.org/python/s...ssignment/

[noisefloor]

Hi,

as already explained @deanhystad, you perform a replacement using a slice operation. If you want to insert something, use the insert method:

>>> some_list = ['apple', 'banana', 'cherry']
>>> another_list = ['kiwi', 'mango']
>>> some_list.insert(1, another_list)
>>> some_list
['apple', ['kiwi', 'mango'], 'banana', 'cherry']
>>>

Please note that a) the list is modified in place and b) it is not exactly doing what you are looking for, as banana is still in the list (could be removed by the pop method of lists.

What you intend to do is possible, but I think only by a bit more slicing and rejoing the list:

>>> some_list = ['apple', 'banana', 'cherry']
>>> another_list = ['kiwi', 'mango']
>>> result = some_list[0:1]
>>> result.append(another_list)
>>> result
['apple', ['kiwi', 'mango']]
>>> result.append(some_list[-1])
>>> result
['apple', ['kiwi', 'mango'], 'cherry']
>>>

Maybe there's a more elegant to do that?

Regards, noisefloor