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Remove unnecessary paragraph, move examples

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y21 2023-08-09 14:48:31 +02:00
parent d2acfb37b3
commit dd25cc349b
1 changed files with 4 additions and 12 deletions
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16
clippy_lints/src/slow_vector_initialization.rs
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@ -29,26 +29,18 @@ declare_clippy_lint! {
/// it involves two operations for allocating and initializing.
/// The `resize` call first allocates memory (since `Vec::new()` did not), and only *then* zero-initializes it.
///
/// Writing `Vec::with_capacity(size)` followed by `vec.resize(len, 0)` is similar.
/// The allocation shifts from `resize` to `with_capacity`,
/// but the zero-initialization still happens separately,
/// when it could be done in one call with `vec![0; len]` (`alloc_zeroed`).
///
/// ### Example
/// ```rust
/// # use core::iter::repeat;
/// # let len = 4;
/// let mut vec1 = Vec::with_capacity(len);
/// let mut vec1 = Vec::new();
/// vec1.resize(len, 0);
///
/// let mut vec1 = Vec::with_capacity(len);
/// vec1.resize(vec1.capacity(), 0);
///
/// let mut vec2 = Vec::with_capacity(len);
/// vec2.extend(repeat(0).take(len));
/// vec2.resize(len, 0);
///
/// let mut vec3 = Vec::new();
/// vec3.resize(len, 0);
/// let mut vec3 = Vec::with_capacity(len);
/// vec3.extend(repeat(0).take(len));
/// ```
///
/// Use instead: