mikecargal

Hands-On Rust: Explain Read<xxx> introduced at end of chapter 7

Title: Hands-On Rust (End of chapter 7)

the query to acquire movers is changed to add Entity (that seems obvious), but point was changed from &mut Point to Read<Point>. ( I understand it’s not necessary to be mutable anymore), and &MovingRandomly is changed to Read<MovingRandomly>.

I don’t recall seeing the Read<xxx> stuff before and think it could use elaboration here.

3 comments

#suggestion /book-hands-on-rust

1 597 3

2020-11-23 18:12:43 UTC

Marked As Solved

herbert

Author of Hands-on Rust

Yes, please. Prior to version 0.3, Legion used a rather wordy syntax that required you to mark every component as Read<MyComponent> or Write<MyComponent>. I’m VERY glad they made it easier to use - but it changed mid-way through the book so everything got updated to the new syntax - or should have done. I’ll do another pass searching for that one.

Post #4

Also Liked

mikecargal

So, both should just use & then?

(Sorry, realized I could answer my own question, and, yep &'s work)

1

Post #3

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