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Hi @sophiedebenedetto,
I propose you a smaller solution:
I think is better because we get rid of additional parameter
new_list
and no need to reverse final result.My first time coding in Elixir. Looks very nice at first glance.
Reminds me of the time when I played with Ruby and Haskell.
Thank you for the post
Awesome! I love this solution, definitely more simple. Thanks for sharing!
Is Elixir able to do this efficiently? In particular, I'm wondering about the callstack, does it keep the frame on the stack while it figures out the RHS of the list, or is it smart enough to build the list element (presumably called
cons
, at least that's what they'd call it in lisp), and then fill in the RHS values as they become available?I seriously didn't know that Elixir had tail call optimization, that is super fkn cool! lol, but now I'm all curious how it works. If you gave these 2 solutions a really long list, I assume the last entry from the blog would be fine, but what about the code in this comment? If it can handle this code without stack overflowing, that would be extremely cool (if it works, then I'm guessing lists would have to have a special case somewhere in the compiler or interpreter).
Not sure I understand. Are you saying that all versions of the function have to have the same arity, so it needs a default value in order to have arity of 1 instead of zero?
My Elixir (1.7.4) didn't have any issue with it. Admittedly, you said it might be an Elixir 2 thing, but still, I'd expect arity to vary across signatures.
Or maybe when you say "declare", it's like a C style declaration, where you're telling the compiler the signature so it can type map a call to a function signature before seeing the definition?
Thanks for pointing these out! I've updated the post to use a header clause for that default argument and included a link to some more info for anyone who wants a deeper understanding of why that's needed.
Your second suggestion looks good too, I'll incorporate a note to that effect in the post later on today.
I see, that makes more sense!
What's the header do / why is it needed?
And I was totally wondering if it could do that with the variable!