The concept of a 0 indexed collection is the norm in programming languages. So, the concept of a 0th element does make sense in that way. Implementation wise things vary, you are right about addresses and the offsets in c. It is an implementation detail. When you talk about linked lists you can have a similar reasoning: How many nodes do you want to walk through to get the desired element? If you say 0 times, then you are referring to the head which is the first element.
minhajuddin
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NobbZ
terakilobyte
Entirely not helpful, but for some reason this discussion reminds me of
“Should array indices start at 0 or 1? My compromise of 0.5 was rejected without, I thought, proper consideration.” – Stan Kelly-Bootle
I think adding an nth function would cause undue confusion. Given a list of [1, 2, 3, 4] the item at position 0 is 1, but 1 is the first element in the list. List.first/1 and List.last/1 already satisfy a specific nth that lexically match how we think about them. List.nth(list, 4) does this grab the 4th item in the list, or the item at position 4?
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michalmuskala
I have no idea why this discussion continues, and where is the confusion. I have no idea where do you expect it to lead by arguing about 0-based and 1-based indexation.
Elixir uses 0-based indexation everywhere. That’s it. There is no confusion what Enum.at(4) returns - the item with index 4, which is the fifth element of the collection.
As I stated in the first post, there’s entirely no reason to introduce List.nth/2 since this is completely covered by Enum.at/2. The performance is also exactly the same for both, as both use exactly the same code when executed on lists. It makes no point to introduce a 1-based list access when access everywhere in elixir, to all indexed structures is 0-based.
Please let’s stop this discussion if there’s nothing constructive to add.
6
ibgib
I just happened upon an early Elixir video mentioned elsewhere on Elixir Forum where this very aspect of uniform indexing is mentioned as a feature at 18:08.
…where this is not supposed to be a feature but…
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OvermindDL1
As a bit of terminology, an index of a collection starts at 1, an offset into a collection starts at 0. Most languages use offset (regardless of what word they use). 
1