rust 常用类型方法分组整理

March 14, 2024

一颗向上的水滴

将 rust 标准库中的几个常用类型的方法安装第一个入参（即：Move、借用、可变借用）分组整理，以便开发时做个参考。

Type	`(..)`	`(self..)`	`(&self..)`	`(&mut self..)`
Cow	`from()`	`into_owned()`		`to_mut()`
Cell	`from()` `from_mut()` `new()`	`into_inner()`	`set()` `get()` `take()` `replace()`	`get_mut()`
RefCell	`from()` `new()`	`into_inner()`	`borrow()` `borrow_mut()` `take()` `replace()`	`get_mut()`
Vec	`from()` `new()` `with_capacity()`	`into_boxed_slice()`	`len()` `capacity()` `is_empyt()`	`insert()` `append()` `push()` `pop()` `remove()` `drain()` `clear()` `splice()` `reserve()` `resize()` `shrink_to()` `truncate()`
BTreeMap	`from()` `new()`	`into_keys()` `range()`	`get()` `len()` `keys()` `values()` `iter()` `get_key_value()` `first_key_value()` `last_key_value()` `contains_key()` `is_empyt()`	`insert()` `append()` `extend` `retain()` `remove()` `pop_first()` `pop_last()` `entry()` `first_entry()` `last_entry()`
HashMap	`from()` `new()`	`keys()` `into_keys()` `capacity()`	`get()` `len()` `values()` `iter()` `is_empty()`	`insert()` `extend` `retain()` `drain()` `remove()` `remove_entry()` `reserve()` `entry()`
Box	`from()` `new()` `leak()` `pin()`	`downcast()` `split()`	`borrow()`	`borrow_mut()` `consume()` `read_line()`

同时还能发现一些规律，比如：

自动解引用的类型还是少数，本文只有 Vec，但手动解引用的基本都会 impl。
同名的方法要注意，比如 Vec 的 len() 和自动解引用后数组的 len()。
一般都会实现个性化的 Clone、Debug、Defaut、Dref、Drop、From 等 Trait，而 Borrow、Into、ToOwned 等使用 Blanket Trait 实现。

Blanket Implementations（一揽子实现）即 Trait 的默认实现，几乎每个类型都实现了下面的“一揽子实现”：

impl	`(..)`	`(self..)`	`(&self..)`	`(&mut self..)`
`impl<T> Any for T`			`type_id()`
`impl<T> Borrow<T> for T`			`borrow()`
`impl<T> BorrowMut<T> for T`				`borrow_mut()`
`impl<T> From<T> for T`	`from()`
`impl<T, U> Into<U> for T`		`into()`
`impl<T> ToOwned for T`			`to_owned()`
`impl<T> ToString for T`			`to_string()`
`impl<T, U> TryFrom<U> for T`	`try_from()`

string

string::String

borrow

borrow::Cow

impl	`(..)`	`(self..)`	`(&self..)`	`(&mut self..)`
Methods
`impl<B> Cow<'_, B>`		`into_owned()`		`to_mut()`
Trait Implementations
`impl<B> Clone for Cow<'_, B>`			`clone()`	`clone_from()`
`impl<B> Deref for Cow<'_, B>`			`deref()`
`impl<'a> Extend<Cow<'a, str>> for String`				`extend()`
`impl From<XXX> for Cow`	`from(XXX)`
`impl From<Cow<XXX> for YYY`	`from(Cow<XXX>)`
Auto Trait Implementations
Blanket Implementations
`impl<T> Any for T`			`type_id()`
`impl<T> Borrow<T> for T`			`borrow()`
`impl<T> BorrowMut<T> for T`				`borrow_mut()`
`impl<T> From<T> for T`	`from()`
`impl<T, U> Into<U> for T`		`into()`
`impl<T> ToOwned for T`			`to_owned()`
`impl<T> ToString for T`			`to_string()`
`impl<T, U> TryFrom<U> for T`	`try_from()`

cell

突破“一个数据只有一个所有者、不可变不允许做可变借用、可变与不可变借用不能同时存在 —— 三大编译器限制”，手工解决共享访问及数据竞争问题。

cell::Cell

impl	`(..)`	`(self..)`	`(&self..)`	`(&mut self..)`
Methods
`impl<T> Cell<T>`	`new(T)`	`into_inner()`	`set()`
			`swap()`
			`replace()`
			`as_slice_of_cells()`
`impl<T> Cell<T>` `where T: Copy`			`get()`
			`update()`
`impl<T> Cell<T>` `where T: ?Sized`	`from_mut()`		`as_ptr()`	`get_mut()`
`impl<T> Cell<T>` `where T: Default`			`take()`
Trait Implementations
`impl<T> Clone for Cell<T>` `where T: Copy`			`clone()`	`clone_from()`
`impl<T> From<T> for Cell<T>`	`from(T)`
Auto Trait Implementations
Blanket Implementations
`impl<T> Any for T`			`type_id()`
`impl<T> Borrow<T> for T`			`borrow()`
`impl<T> BorrowMut<T> for T`				`borrow_mut()`
`impl<T> From<T> for T`	`from()`
`impl<T> ToOwned for T`			`to_owned()`
`impl<T, U> TryFrom<U> for T`	`try_from()`

cell::RefCell

impl	`(..)`	`(self..)`	`(&self..)`	`(&mut self..)`
Methods
`impl<T> RefCell<T>`	`new(T)`	`into_inner()`	`replace()`
			`replace_with()`
			`swap()`
`impl<T> RefCell<T>` `where T: ?Sized`			`borrow()`	`get_mut()`
			`try_borrow()`	`undo_leak()`
			`borrow_mut()`
			`try_borrow_mut()`
`impl<T> RefCell<T>` `where T: Default`			`take()`
Trait Implementations
`impl<T> Clone for RefCell<T>` `where T: Clone`			`clone()`	`clone_from()`
`impl<T> From<T> for Cell<T>`	`from(T)`
Auto Trait Implementations
Blanket Implementations
`impl<T> Any for T`			`type_id()`
`impl<T> Borrow<T> for T`			`borrow()`
`impl<T> BorrowMut<T> for T`				`borrow_mut()`
`impl<T> From<T> for T`	`from()`
`impl<T, U> Into<U> for T`		`into()`
`impl<T> ToOwned for T`			`to_owned()`
`impl<T, U> TryFrom<U> for T`	`try_from()`

vec

vec::Vec

impl	`(..)`	`(self..)`	`(&self..)`	`(&mut self..)`
Methods
`impl<T> Vec<T, Global>`	`new()`
	`with_capacity()`
`impl<T, A> Vec<T, A>`	`new_in(A)`		`capacity()`	`reserve()`
				`try_reserve()`
				`shrink_to_fit()`
				`shrink_to()`
				`truncate()`
		`into_boxed_slice()`	`as_slice()`	`as_mut_slice()`
			`as_ptr()`	`as_mut_ptr()`
			`len()`	`insert()`
			`is_empty()`	`remove()`
				`retain()`
				`push()`
				`pop()`
				`append()`
				`drain()`
				`clear()`
				`split_off()`
`impl<T, A> Vec<T, A>` `where T:Clone`				`resize()`
`impl<T, A> Vec<T, A>` `where A:Allocator`				`splice()`
`Deref<Target = [T]>` 自动解引用			``len()``
	（略）	（略）	（略）	（略）
Trait Implementations
`impl<T, A> AsMut<[T]> for Vec<T, A>`				`as_mut()`
`impl<T, A> AsRef<[T]> for Vec<T, A>`			`as_ref()`
`impl<T, A> Clone for Vec<T, A>`			`clone()`	`clone_from()`
`impl<T, A> Deref for Vec<T, A>`			`deref()` 手工解引用
`impl<T, A> DerefMut for Vec<T, A>`				`deref_mut()`
`impl<T, A> Drop for Vec<T, A>`				`drop()`
`impl<T> From<XXX> for Vec<T, Global>`	`from(XXX)`
`impl<T> From<Vec<XXX>> for YYY`	`from(<Vec<XXX>>)`
`impl<T, A> Hash for Vec<T, A>`		`hash()`
		`hash_slice()`
`impl<'a, T, A> Extend<&'a T> for Vec<T, A>`				`extend()`
Auto Trait Implementations
Blanket Implementations
`impl<T> Any for T`			`type_id()`
`impl<T> Borrow<T> for T`			`borrow()`
`impl<T> BorrowMut<T> for T`				`borrow_mut()`
`impl<T> From<T> for T`	`from()`
`impl<T, U> Into<U> for T`		`into()`
`impl<T> ToOwned for T`			`to_owned()`
`impl<T, U> TryFrom<U> for T`	`try_from()`

collections

collections::BTreeMap

impl	`(..)`	`(self..)`	`(&self..)`	`(&mut self..)`
Methods
`impl<K, V> BTreeMap<K, V, Global>`	`new()`
`impl<K, V, A> BTreeMap<K, V, A>`		`into_keys()`	`get()`	`clear()`
			`get_key_value()`	`pop_first()`
			`first_key_value()`	`first_entry()`
			`last_key_value()`	`last_entry()`
			`contains_key()`	`pop_last()`
			`len()`	`get_mut()`
			`is_empyt()`	`insert()`
				`remove()`
				`retain()`
				`append()`
		`range()`		`range_mut()`
			`keys()`	`entry()`
				`split_off()`
			`iter()`	`iter_mut()`
			`values()`	`values_mut()`
Trait Implementations
`impl<K, V, A> Clone for BTreeMap<K, V, A>`			`clone()`
`impl<K, V, A> Extend<(K, V)> for BTreeMap<K, V, A>`				`extend()`
				`extend_one()`
				`extend_reserve()`
`impl ... From<..> for HashMap<..>`	`from(arr: [(K, V); N])`
Auto Trait Implementations
Blanket Implementations
`impl<T> Any for T`			`type_id()`
`impl<T> Borrow<T> for T`			`borrow()`
`impl<T> BorrowMut<T> for T`				`borrow_mut()`
`impl<T> From<T> for T`	`from()`
`impl<T, U> Into<U> for T`		`into()`
`impl<T> ToOwned for T`			`to_owned()`
`impl<T, U> TryFrom<U> for T`	`try_from()`

collections::HashMap

impl	`(..)`	`(self..)`	`(&self..)`	`(&mut self..)`
Methods
`impl<K, V> HashMap<K, V, RandomState>`	`new()`
`impl<K, V, S> HashMap<K, V, S>`		`capacity()`
		`keys()`	`values()`	`values_mut()`
		`into_keys()`	`is_empty()`	`drain()`
		`into_values()`	`len()`	`drain_filter()`
			`iter()`	`iter_mut()`
				`retain()`
			`hasher()`	`clear()`
`impl<K, V, S> HashMap<K, V, S>`				`reserve()`
			`get_key_value()`	`shrink_to_fit()`
			`contains_key()`	`shrink_to()`
				`entry()`
			`get()`	`get_mut()`
				`insert()`
				`remove()`
				`remove_entry()`
Trait Implementations
`impl<K, V, A> Clone for HashMap<K, V, A>`			`clone()`
`impl<K, V, A> Extend<(K, V)> for HashMap<K, V, A>`				`extend()`
				`extend_one()`
				`extend_reserve()`
`impl ... From<..> for HashMap<..>`	`from(arr: [(K, V); N])`




Auto Trait Implementations
Blanket Implementations
`impl<T> Any for T`			`type_id()`
`impl<T> Borrow<T> for T`			`borrow()`
`impl<T> BorrowMut<T> for T`				`borrow_mut()`
`impl<T> From<T> for T`	`from()`
`impl<T, U> Into<U> for T`		`into()`
`impl<T> ToOwned for T`			`to_owned()`
`impl<T, U> TryFrom<U> for T`	`try_from()`

boxed

boxed::Box

impl	`(..)`	`(self..)`	`(&self..)`	`(&mut self..)`
Methods
`impl<T> Box<T, Global>`	`new(T)`
	`pin(T)`
`impl<T> Box<T, Global>`	`from_raw(T)`
	`into_raw()`
	`leak()`
`impl<A> Box<dyn Any + 'static, A>`		`downcast()`
Trait Implementations
`impl<T, A> Borrow<T> for Box<T, A>`			`borrow()`
`impl<T, A> BorrowMut<T> for Box<T, A>`				`borrow_mut()`
`impl<B: BufRead + ?Sized> BufRead for Box<B>`		`split()`		`fill_buf()`
		`line()`		`consume()`
				`read_until()`
				`read_line()`
`impl ... From<XXX> for Box<..>`	`from(XXX)`
`impl ... From<Box<XXX>> for xxx`	`from(Box<XXX>)`
Auto Trait Implementations
Blanket Implementations
`impl<T> Any for T`			`type_id()`
`impl<T> Borrow<T> for T`			`borrow()`
`impl<T> BorrowMut<T> for T`				`borrow_mut()`
`impl<T> From<T> for T`	`from()`
`impl<T, U> Into<U> for T`		`into()`
`impl<F> IntoFuture for F`		`into_future()`
`impl<T> ToOwned for T`			`to_owned()`
`impl<T> ToString for T`		`to_string()`
`impl<T, U> TryFrom<U> for T`	`try_from()`

string​

string::String​

borrow​

borrow::Cow​

cell​

cell::Cell​

cell::RefCell​

vec​

vec::Vec​

collections​

collections::BTreeMap​

collections::HashMap​

boxed​

boxed::Box​