A-lintL-perfT-middlegood first issue
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Descrizione
What it does
Suggest using StdinLock rather than BufReader::new(io::stdin()) since it is already buffered. We might also want to take care of let stdin = io::stdin(); BufReader::new(stdin) and also BufReader::new(stdinlock) (there could be people doing this).
Categories (optional)
- Kind: perf
Locking stdin also provide benefit for not having to re-lock it on every read.
std::io::stdin() already is buffered. Re-buffering it only increase the memcpy calls.
Source https://users.rust-lang.org/t/correct-way-for-taking-large-input-from-keyboard/55304/11 Related to https://github.com/rust-lang/rust-clippy/issues/1805
For example:
- Recommend locking of stdin to reduce re-locking
- Suggest not re-buffering stdin lock which already implements
BufRead
Drawbacks
None.
Example
let reader = BufReader::new(io::stdin()); // this could a separate variable or StdinLock
Could be written as:
let stdin = io::stdin();
let reader = stdin.lock();