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I got a list of objects which look like strings, but are not real strings (think about mmap'ed files). Like this:
x = [ "abc", "defgh", "ij" ]
What i want is x to be directly indexable like it was a big string, i.e.:
(x[4] == "e") is True
(Of course I don't want to do "".join(x) which would merge all strings, because reading a string is too expensive in my case. Remember it's mmap'ed files.).
This is easy if you iterate over the entire list, but it seems to be O(n). So I've implemented __getitem__ more efficiently by creating such a list:
x = [ (0, "abc"), (3, "defgh"), (8, "ij") ]
Therefore I can do a binary search in __getitem__ to quickly find the tuple with the right data and then indexing its string. This works quite well.
I see how to implement __setitem__, but it seems so boring, I'm wondering if there's not something that already does that.
To be more precise, this is how the data structure should honor __setitem__:
>>> x = [ "abc", "defgh", "ij" ]
>>> x[2:10] = "12345678"
>>> x
[ "ab", "12345678", "j" ]
I'd take any idea about such a data structure implementation, name or any hint.
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In Python, lists are represented by square brackets. Therefore, we create a list as follows. The above list, colors is stored in memory as shown below. We can also create a list that contains multiple data types, like strings, integers, and floats.
To create a list of strings, first use square brackets [ and ] to create a list. Then place the list items inside the brackets separated by commas. Remember that strings must be surrounded by quotes. Also remember to use = to store the list in a variable.
To find the index of a list element in Python, use the built-in index() method. To find the index of a character in a string, use the index() method on the string. This is the quick answer.
In Python, lists are ordered collections of items that allow for easy use of a set of data. List values are placed in between square brackets [ ] , separated by commas.
What you are describing is a special case of the rope data structure.
Unfortunately, I am not aware of any Python implementations.
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