slicing question: rawdata[j:j+1] == 'xx' #will this ever be true ??

[richard.hsu]

I am new to python language and most of my python programming has been
done with IronPython.

I was looking at the source of markupbase.py which is included with
Python 2.4 and came across the following line of code:-

if rawdata[j:j+1] == '--': #comment

i was confused because based on my understanding of the slicing syntax,
rawdata[j:j+1] will either yield a string with ONE character or an
empty string, therefore this boolean comparison will always be False
because we are checking if it will be equal to a string with 2
characters!

am I missing something here ?

thank you in advance for educating me.

 

[Fredrik Lundh]

I am new to python language and most of my python programming has been
done with IronPython.

I was looking at the source of markupbase.py which is included with
Python 2.4 and came across the following line of code:-

if rawdata[j:j+1] == '--': #comment

i was confused because based on my understanding of the slicing syntax,
rawdata[j:j+1] will either yield a string with ONE character or an
empty string, therefore this boolean comparison will always be False
because we are checking if it will be equal to a string with 2
characters!

am I missing something here ?

nope.

it's a bug, and it's fixed in 2.5 alpha, so there's no need to report it.

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