ziglang
BoundedArray: add a len() function to get the length as a usize
The type of the active length was changed to the smallest possible type, which is nice to get a more compact representation.
However, that change introduced unexpected side effects. For example, a.len + b.len can now trigger an integer overflow.
There's also an inconsistency between functions that set the size, which all use a usize, and the way to read the size, that uses a different type. This is also inconsistent with pretty much anything else that represents a slice length.
Replace .len with len(), a function that returns the length as a usize to minimize surprise and simplify application code.
Originally suggested by @matklad
not sure this is worth is worth the complexity for the common case given that unless the whole array fits in less than 8 bytes there will be a massive amount of struct padding the usize can fit into
oh the change i thought this was, it seems was made 5 months ago. my suggestion would be to make the .len field itself a usize
oh the change i thought this was, it seems was made 5 months ago. my suggestion would be to make the
.lenfield itself a usize
It used to be a usize. The change was made in #16299 .
Since the length is small, it can usually fit in 1 or 2 bytes. So, a handful bytes are frequently saved, especially when the element type is a u8.
I don't like this change. I think it's a bandage over a language design flaw and I'd rather treat the wound directly. I'd like to let this sit for the time being.
This is the wrong solution to the problem. This will be resolved in one of two ways instead:
- Reverting #16299, leaving users to do this size optimization themselves if necessary.
- Accepting #3806
I proceeded with the revert for the time being (85747b266aac8a2ff7fea4a4b18f722133544ad7).