Beginner question regarding `use ...as`

#1

Here https://crates.io/crates/ahash it is said that for convenience one could do

use ahash::AHashMap;

let mut map: AHashMap<i32, i32> = AHashMap::new();
map.insert(12, 34);
map.insert(56, 78);

But one could do the following which looks even more convenient to me.

use ahash::{AHashMap as HashMap};

let mut map: HashMap<i32, i32> = HashMap::new();
map.insert(12, 34);
map.insert(56, 78);

Question: Is my version technically the same as the one given by the author of ahash?

#2

Technically, yes. The only possible difference would be if you've named the import the same as some item from the prelude, i.e. Vec or Result, since in this case explicit import would shadow the implicit one.

3 Likes
#3

Or you could shadow items from glob imports.

I.e.

use std::collections::*;
use ahash::{AHashMap as HashMap};

Will pick ahash's version, not the std version

#4

BTW, you can write this without the brackets:

use ahash::AHashMap as HashMap;

The brackets are for grouping, so that you can do things like this:

use ahash::{AHashmap as HashMapA, BHashMap as HashMapB};
1 Like
#5

@skysch Oh yes, thank you.