Correct way to split a string


In python I can do test = “A string”.split(" ")[1] And then the value of test will be “string”. How can I correctly do this in rust? I have fair knowledge with rust but I never quite understood how splitting strings work.


this forum is about language discussion, please post this kind of questions to stackoverflow.

in rust the split function returns a lazy iterator. you cannot index lazy iterators (why i don’t know, would be trivial to implement). so you need to use the function nth. an example on playpen is here:


Oh alright. Thank you.


It would only be trivial (and correct) to implement on iterators that implement RandomAccessIterator.


why? as long as you only implement Index and forward the call to nth, you get the expected behaviour.


Then you’ll have users asking you why this doesn’t work:

 let mut spl = "x y z".split(' ');
 let a = spl[1];
 let b = spl[2];

Or maybe it does work, if the split iterator is Copy? But then we can fool users into O(N^2) algorithms.


hmm right… lets not do that. we can always collect and index :slight_smile:

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