Vendor std::io::Cursor as buf::Cursor (closes #75) #146
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Extracts the minimal parts of std::io::Cursor needed to support bytes use cases. This is needed to support no_std as std::io is unavailable in these contexts. It also (arguably) improves the API ergonomics by simplifying imports. Per notes on tokio-rs#75, changes the u64 position to a u32 to save space.
| pub fn set_position(&mut self, pos: u32) { self.pos = pos; } | ||
| } | ||
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| impl<T> Read for Cursor<T> where T: AsRef<[u8]> { |
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The Read and BufRead impls here aren't actually used by bytes at all. I have included them as without them the following example fails:
That said, perhaps people are expecting them? (and possibly Write as well?)
| @@ -15,8 +15,7 @@ use std::{cmp, io, ptr}; | |||
| /// The simplest `Buf` is a `Cursor` wrapping a `[u8]`. | |||
| /// | |||
| /// ``` | |||
| /// use bytes::Buf; | |||
| /// use std::io::Cursor; | |||
| /// use bytes::{Buf, Cursor}; | |||
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I think this is a nice ergonomic improvement over:
use bytes::Buf;
use std::io::Cursor;
| #[derive(Clone, Debug)] | ||
| pub struct Cursor<T> { | ||
| inner: T, | ||
| pos: u32, |
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This is a u64 in std::io, however @alexcrichton suggested using a smaller type here: #75 (comment)
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Note this is a breaking API change which means it can't be landed until bytes 0.5. |
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In the technical sense this is unfortunately still a breaking change because Whether it's actually breaking in a practical sense is a different question, though, which I'm not sure about. |
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Yeah, duly noted this is a breaking change. I'm also uncertain it's the best path forward. |
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After talking with @carllerche it sounds like if a breaking change is to happen here, it would probably be better to get rid of cursors altogether. |
Extracts the minimal parts of std::io::Cursor needed to support bytes use cases.
This is needed to support no_std as std::io is unavailable in these contexts.
It also (arguably) improves the API ergonomics by simplifying imports.
Per notes on #75, changes the u64 position to a u32 to save space.