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Comment by abaga129 | Hacker News Reader

Having to use .array() on the Result of some functions is the exact same problem I've ran into as well! D is by far my favorite language but there is definitely some room for improvement in terms of documentation on how to use the standard library.

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On the other hand, I like the explicitness of it instead of automatically converting to a different type. At least you know exactly what it's doing.

The python version of it would be calling `list()` on things all the time, which you might not always want to do.

That's a fair point. I'm not necessarily against having to do it, I just would like there to be a more obvious indication of how to convert the result to an array. It took a lot of searching the first time I came across this.

Perhaps it's just my own incompetence though!

It's definitely not your incompetence. I started learning D a few months ago and it didn't click until someone on IRC explained it clearly to me. It's not in the tutorial or anything unless I missed it.

It is the first thing I added to my articles when I introduced range based operations :

https://dev.to/jessekphillips/count-of-a-list-in-d-49k4

It's not the best idea to always unconditionally use .array because you might want to preserve the laziness of a Result type. By using .array you're saying you want all of the results into memory right now! Depending on what you're doing, you might not want that.

I actually didn't know this! Very cool. I guess it's similar to calling .ToList() on IEnumerable<T> in C#.

Most range function return a "Voldemort" that preserve lazyness if you put it in an `auto` local. Or you can use .array to get a slice out of it.

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