64 lines
1.6 KiB
Rust
64 lines
1.6 KiB
Rust
use std::iter::repeat;
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fn main() {
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resize_vector();
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extend_vector();
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mixed_extend_resize_vector();
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}
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fn extend_vector() {
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// Extend with constant expression
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let len = 300;
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let mut vec1 = Vec::with_capacity(len);
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vec1.extend(repeat(0).take(len));
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// Extend with len expression
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let mut vec2 = Vec::with_capacity(len - 10);
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vec2.extend(repeat(0).take(len - 10));
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// Extend with mismatching expression should not be warned
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let mut vec3 = Vec::with_capacity(24322);
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vec3.extend(repeat(0).take(2));
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}
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fn mixed_extend_resize_vector() {
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// Mismatching len
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let mut mismatching_len = Vec::with_capacity(30);
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mismatching_len.extend(repeat(0).take(40));
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// Slow initialization
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let mut resized_vec = Vec::with_capacity(30);
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resized_vec.resize(30, 0);
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let mut extend_vec = Vec::with_capacity(30);
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extend_vec.extend(repeat(0).take(30));
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}
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fn resize_vector() {
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// Resize with constant expression
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let len = 300;
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let mut vec1 = Vec::with_capacity(len);
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vec1.resize(len, 0);
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// Resize mismatch len
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let mut vec2 = Vec::with_capacity(200);
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vec2.resize(10, 0);
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// Resize with len expression
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let mut vec3 = Vec::with_capacity(len - 10);
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vec3.resize(len - 10, 0);
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// Reinitialization should be warned
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vec1 = Vec::with_capacity(10);
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vec1.resize(10, 0);
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}
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fn do_stuff(vec: &mut [u8]) {}
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fn extend_vector_with_manipulations_between() {
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let len = 300;
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let mut vec1: Vec<u8> = Vec::with_capacity(len);
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do_stuff(&mut vec1);
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vec1.extend(repeat(0).take(len));
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}
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