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数组个数限制问题

yuyi98 发表于 2019-03-14 22:24

Tags：array, iterator

fn main() { let a = [1.5f32; 50]; for i in &a { println!("{}", i); } }

error[E0277]: &[f32; 50] is not an iterator --> src\main.rs:3:11 | 3 | for i in &a { | ^^ &[f32; 50] is not an iterator | = help: the trait std::iter::Iterator is not implemented for &[f32; 50] = note: required by std::iter::IntoIterator::into_iter

如果数组个数修改为32及以下（如[1.5f32; 31]）就没有问题，请解释一下！

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gaxxx 2019-03-15 10:32

那是不是这么写也还行。。。

use std::iter::repeat

repeat(1.5f32).take(50)
Mike Tang 2019-03-15 00:13

因为 Rust 目前还的数组迭代器定义很奇葩，是手动实现的，只实现到了32个，因为还没有number泛型，没法自动实现。

具体可参阅：https://doc.rust-lang.org/std/primitive.array.html

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