rust - 从字符迭代器添加路径组件而不先收集它的惯用方式是什么？

Question

例如。:

// just an example, can be any Iterator<Item = char>
let iter = "hello".chars();

let mut path = std::path::PathBuf::new();

// works but is inefficient
path.push(iter.collect::<String>());

// does not work:
//   path.push(iter);
// if path were String we could do
//   path.extend(iter)
println!("{:?}", path);

Answer 1

从任意字符的迭代器转换为PathBuf的最佳方法是先将迭代器收集到String中:

let path_buf = PathBuf::from(iter.collect::<String>());

虽然从字面上看这并不能避免先收集迭代器，但是在创建 String时，它只会分配一次内存。如 documentation中所述，此内存已被PathBuf重用:

Converts a String into a PathBuf

This conversion does not allocate or copy memory.