['a', 'b'][True] results 'b' But how?

[kath]

Hi,

Can any one please tell me how is the following code is working?
['a','b'] is a list of string, and [True] is list of boolean value.
How is it making effect....?

['a','b] [True] 'b'
['a','b'] [False] 'a'
['a','b']['some_string' == r'some_string'] 'b'
['a','b']['some_string' == r'somestring']

'a'

<code>


Thanks in advance,
regards,
kath.

 

[Kelvie Wong]

In this case, [True] and [False] are not lists, rather you're
accessing the items of the list with the index True or False, as per
the following example:

a_list = ['a', 'b']
a_list[True] 'b'
a_list[False]

'a'

This happens because the __getitem__ method takes its argument (which
in this case is True or False) and casts it into an integer:
0

So thus it follows logically that since:

a_list[1] 'b'
a_list[0]

'a'

a_list[True] and a_list[False] must be its first and zeroth indexed
members, respectively.

Hi,

Can any one please tell me how is the following code is working?
['a','b'] is a list of string, and [True] is list of boolean value.
How is it making effect....?

['a','b] [True] 'b'
['a','b'] [False] 'a'
['a','b']['some_string' == r'some_string'] 'b'
['a','b']['some_string' == r'somestring']

'a'

<code>


Thanks in advance,
regards,
kath.

 

[Robert Bauck Hamar]

Hi,

Can any one please tell me how is the following code is working?
['a','b'] is a list of string
Yes.

and [True] is list of boolean value.

No. It's the subscription operator applied to the list of strings.
a = ['a', 'b']
a[True]
may be clearer.

How is it making effect....?

['a','b] [True] 'b'
['a','b'] [False] 'a'
['a','b']['some_string' == r'some_string'] 'b'
['a','b']['some_string' == r'somestring']

'a'

<code>

 

[kath]

Hi Kelvie and RBH,

Thanks for your quick reply. That was very much helpful indeed.

regards,
kath.