Before Go had iterators, you either had callbacks or channels to decompose work.
If you have a lot of files on a local ssd, and you're doing nothing interesting with the tree entries, it's a lot of work for no payoff. You're better off just passing a callback function.
If you're walking an NFS directory hierarchy and the computation on each entry is substantial then there's value in it because you can run computations while waiting on the potentially slow network to return results.
In the case of the callback, it is a janky interface because you would need to partially apply the function you want to do the work or pass a method on a custom struct that holds state you're trying to accumulate.
Now that iterators are becoming a part of the language ecosystem, one can use an iterator to decompose the walking and the computation without the jank of a partially applied callback and without the overhead of a channel.
Before Go had iterators, you either had callbacks or channels to decompose work.
If you have a lot of files on a local ssd, and you're doing nothing interesting with the tree entries, it's a lot of work for no payoff. You're better off just passing a callback function.
If you're walking an NFS directory hierarchy and the computation on each entry is substantial then there's value in it because you can run computations while waiting on the potentially slow network to return results.
In the case of the callback, it is a janky interface because you would need to partially apply the function you want to do the work or pass a method on a custom struct that holds state you're trying to accumulate.
Now that iterators are becoming a part of the language ecosystem, one can use an iterator to decompose the walking and the computation without the jank of a partially applied callback and without the overhead of a channel.