Zen

Translation

Erases the element with key equivalent to `k` if it exists.
21/590 · 59

Sign in to save translations.

Key English Chinese (Simplified Han script) Actions
The interface is exposition only, as C++ does not allow to declare parameters `f1` and `f2` after a variadic parameter pack.
该接口仅为说明性用途，因为C++不允许在可变参数包之后声明`f1`和`f2`参数。
The `template<class K, class\... Args, class F1, class F2>` overloads only participate in overload resolution if `Hash::is_transparent` and `Pred::is_transparent` are valid member typedefs. The library assumes that `Hash` is callable with both `K` and `Key` and that `Pred` is transparent. This enables heterogeneous lookup which avoids the cost of instantiating an instance of the `Key` type.
若`Hash::is_transparent`和`Pred::is_transparent`是有效的成员类型别名，则`template<class k,="" args,="" class="" f1,="" f2="">`重载版本才会参与重载决议。库假定`Hash`可同时接受`K`与`Key`类型的参数调用，且`Pred`是透明的。这支持异构查找，避免了实例化`Key`类型对象的开销。</class>
:1369
--
--
:1371
---
---
insert_or_assign
insert_or_assign
```c++ template<class M> bool insert_or_assign(const key_type& k, M&& obj); template<class M> bool insert_or_assign(key_type&& k, M&& obj); template<class K, class M> bool insert_or_assign(K&& k, M&& obj); ```
```c++ template<class m=""> bool insert_or_assign(const key_type&amp; k, M&amp;&amp; obj); template<class m=""> bool insert_or_assign(key_type&amp;&amp; k, M&amp;&amp; obj); template<class k,="" class="" m=""> bool insert_or_assign(K&amp;&amp; k, M&amp;&amp; obj); ```</class></class></class>
Inserts a new element into the table or updates an existing one by assigning to the contained value.
向容器插入新元素，或通过赋值给容器内已存值来更新现有元素。
If there is an element with key `k`, then it is updated by assigning `std::forward<M>(obj)`.
若容器中存在键为`k`的元素，则通过`std::forward<m>(obj)`赋值来更新该元素。</m>
If there is no such element, it is added to the table as: ```c++
若不存在该元素，则将其以如下形式添加到容器中：
value_type(std::piecewise_construct, std::forward_as_tuple(std::forward<Key>(k)), std::forward_as_tuple(std::forward<M>(obj)))
value_type(std::piecewise_construct, std::forward_as_tuple(std::forward<key>(k)), std::forward_as_tuple(std::forward<m>(obj)))</m></key>
value_type(std::piecewise_construct, std::forward_as_tuple(std::forward<K>(k)), std::forward_as_tuple(std::forward<M>(obj))) ```
value_type(std::piecewise_construct, std::forward_as_tuple(std::forward<k>(k)), std::forward_as_tuple(std::forward<m>(obj))) ```</m></k>
Returns:;; `true` if an insert took place. Concurrency:;; Blocking on rehashing of `*this`. Notes:;; Invalidates pointers and references to elements if a rehashing is issued. + + The `template<class K, class M>` only participates in overload resolution if `Hash::is_transparent` and `Pred::is_transparent` are valid member typedefs. The library assumes that `Hash` is callable with both `K` and `Key` and that `Pred` is transparent. This enables heterogeneous lookup which avoids the cost of instantiating an instance of the `Key` type.
返回值：插入成功时返回`true`。
并发：执行重哈希操作时会阻塞当前对象`*this`。
说明：若触发重哈希，将使指向元素的指针和引用失效。
`template<class k,="" class="" m="">` 仅当 `Hash::is_transparent` 和 `Pred::is_transparent` 为有效成员类型别名时才参与重载决议。库假定`Hash`可同时接受`K`与`Key`类型参数调用，且`Pred`是透明的。这支持异构查找，避免了实例化`Key`类型对象的开销。</class>
:1404
---
---
erase
擦除
```c++ size_type erase(const key_type& k); template<class K> size_type erase(const K& k); ```
```c++ size_type erase(const key_type&amp; k); template<class k=""> size_type erase(const K&amp; k); ```</class>
Erases the element with key equivalent to `k` if it exists.
若存在键等价于`k`的元素，则删除该元素。
Returns:;; The number of elements erased (0 or 1). Throws:;; Only throws an exception if it is thrown by `hasher` or `key_equal`. Notes:;; The `template<class K>` overload only participates in overload resolution if `Hash::is_transparent` and `Pred::is_transparent` are valid member typedefs. The library assumes that `Hash` is callable with both `K` and `Key` and that `Pred` is transparent. This enables heterogeneous lookup which avoids the cost of instantiating an instance of the `Key` type.
返回值：删除的元素数量（0 或 1）。
异常：仅当哈希函数`hasher`或键比较函数`key_equal`抛出异常时才会抛出异常。
说明：仅当`Hash::is_transparent`和`Pred::is_transparent`为有效的成员类型别名时，`template<class k="">`重载版本才参与重载决议。库假定`Hash`可同时接受`K`与`Key`类型的参数调用，且`Pred`是透明的。该设计支持异构查找，避免了实例化`Key`类型对象的开销。</class>
:1419
---
---
erase_if by Key
erase_if by Key
```c++ template<class F> size_type erase_if(const key_type& k, F f); template<class K, class F> size_type erase_if(const K& k, F f); ```
```c++ template<class f=""> size_type erase_if(const key_type&amp; k, F f); template<class k,="" class="" f=""> size_type erase_if(const K&amp; k, F f); ```</class></class>
Erases the element `x` with key equivalent to `k` if it exists and `f(x)` is `true`.
若存在键与 `k` 等价的元素 `x`，且 `f(x)` 返回 `true`，则删除该元素。
Returns:;; The number of elements erased (0 or 1). Throws:;; Only throws an exception if it is thrown by `hasher`, `key_equal` or `f`. Notes:;; `f` is passed a non-const reference to `x`. + + The `template<class K, class F>` overload only participates in overload resolution if `std::is_execution_policy_v<std::remove_cvref_t<ExecutionPolicy>>` is `false`. + + The `template<class K, class F>` overload only participates in overload resolution if `Hash::is_transparent` and `Pred::is_transparent` are valid member typedefs. The library assumes that `Hash` is callable with both `K` and `Key` and that `Pred` is transparent. This enables heterogeneous lookup which avoids the cost of instantiating an instance of the `Key` type.
返回值：删除的元素数量（0 或 1）。
异常：仅当哈希函数`hasher`、键比较函数`key_equal`或函数`f`抛出异常时才会抛出异常。
说明：`f`接收元素`x`的非常量引用。

仅当`std::is_execution_policy_v<std::remove_cvref_t<executionpolicy>&gt;`为`false`时，`template<class k,="" class="" f="">`重载版本才参与重载决议。

仅当`Hash::is_transparent`和`Pred::is_transparent`为有效的成员类型别名时，`template<class k,="" class="" f="">`重载版本才参与重载决议。库假定`Hash`可同时接受`K`与`Key`类型的参数调用，且`Pred`是透明的。该设计支持异构查找，避免了实例化`Key`类型对象的开销。</class></class></std::remove_cvref_t<executionpolicy>
:1438
---
---
:1440
erase_if
erase_if
```c++ template<class F> size_type erase_if(F f); ```
```c++ template<class f=""> size_type erase_if(F f); ```</class>
Successively invokes `f` with non-const references to each of the elements in the table, and erases those for which `f` returns `true`.
依次以非常量引用为参数，对容器中的每个元素调用`f`，并删除所有`f`返回`true`的元素。
Returns:;; The number of elements erased. Throws:;; Only throws an exception if it is thrown by `f`.
返回值：被删除的元素数量。
异常：仅当函数 `f` 抛出异常时才会抛出异常。
:1451
---
---
Parallel erase_if
并行条件擦除
```c++ template<class ExecutionPolicy, class F> void erase_if(ExecutionPolicy&& policy, F f); ```
```c++ template<class executionpolicy,="" class="" f=""> void erase_if(ExecutionPolicy&amp;&amp; policy, F f); ```</class>
Invokes `f` with non-const references to each of the elements in the table, and erases those for which `f` returns `true`. Execution is parallelized according to the semantics of the execution policy specified.
依次以非常量引用为参数，对容器中的每个元素调用`f`，并删除所有`f`返回`true`的元素。执行过程将根据指定的执行策略语义进行并行化处理。
English Chinese (Simplified Han script) Actions
Copy Insert
复制插入
Synopsis
概要
Description
描述
Chunk size internally used in xref:concurrent_flat_map_bulk_visit[bulk visit] operations.
xref:concurrent_flat_map_bulk_visit [批量访问] 操作内部使用的块大小。
The move constructor. The internal bucket array of `other` is transferred directly to the new table. The hash function, predicate and allocator are moved-constructed from `other`. If statistics are xref:concurrent_flat_map_boost_unordered_enable_stats[enabled], transfers the internal statistical information from `other` and calls `other.reset_stats()`.
移动构造函数。other 的内部桶数组会直接转移到新表中。哈希函数、谓词和分配器均从 other 移动构造而来。如果启用了 xref:concurrent_flat_map_boost_unordered_enable_stats [统计功能]，则从 other 转移内部统计信息，并调用 other.reset_stats()。
Move Constructor with Allocator
带分配器的移动构造函数
Insert Initializer List
初始化列表插入
```c++ template<class InputIterator,class F> size_type insert_or_visit(InputIterator first, InputIterator last, F f); template<class InputIterator,class F> size_type insert_or_cvisit(InputIterator first, InputIterator last, F f); ```
```c++ template<class inputiterator,class="" f=""> size_type insert_or_visit(InputIterator first, InputIterator last, F f); template<class inputiterator,class="" f=""> size_type insert_or_cvisit(InputIterator first, InputIterator last, F f); ```</class></class>
Insert Iterator Range and Visit
迭代器范围插入并访问
```c++ template<class... Args> bool try_emplace(const key_type& k, Args&&... args); template<class... Args> bool try_emplace(key_type&& k, Args&&... args); template<class K, class... Args> bool try_emplace(K&& k, Args&&... args); ```
```c++ template<class... args=""> bool try_emplace(const key_type&amp; k, Args&amp;&amp;... args); template<class... args=""> bool try_emplace(key_type&amp;&amp; k, Args&amp;&amp;... args); template<class k,="" class...="" args=""> bool try_emplace(K&amp;&amp; k, Args&amp;&amp;... args); ```</class></class...></class...>
unlike xref:#concurrent_flat_map_emplace[emplace], which simply forwards all arguments to ``value_type``'s constructor.
这与 xref:#concurrent_flat_map_emplace [emplace] 不同，后者仅将所有参数转发给value_type的构造函数。
insert_or_assign
insert_or_assign
If there is no such element, it is added to the table as: ```c++
若不存在该元素，则将其以如下形式添加到容器中：
value_type(std::piecewise_construct, std::forward_as_tuple(std::forward<Key>(k)), std::forward_as_tuple(std::forward<M>(obj)))
value_type(std::piecewise_construct, std::forward_as_tuple(std::forward<key>(k)), std::forward_as_tuple(std::forward<m>(obj)))</m></key>
value_type(std::piecewise_construct, std::forward_as_tuple(std::forward<K>(k)), std::forward_as_tuple(std::forward<M>(obj))) ```
value_type(std::piecewise_construct, std::forward_as_tuple(std::forward<k>(k)), std::forward_as_tuple(std::forward<m>(obj))) ```</m></k>
Erases the element with key equivalent to `k` if it exists.
若存在键等价于`k`的元素，则删除该元素。
Erases the element `x` with key equivalent to `k` if it exists and `f(x)` is `true`.
若存在键与 `k` 等价的元素 `x`，且 `f(x)` 返回 `true`，则删除该元素。
```c++ template<class ExecutionPolicy, class F> void erase_if(ExecutionPolicy&& policy, F f); ```
```c++ template<class executionpolicy,="" class="" f=""> void erase_if(ExecutionPolicy&amp;&amp; policy, F f); ```</class>
Invokes `f` with non-const references to each of the elements in the table, and erases those for which `f` returns `true`. Execution is parallelized according to the semantics of the execution policy specified.
依次以非常量引用为参数，对容器中的每个元素调用`f`，并删除所有`f`返回`true`的元素。执行过程将根据指定的执行策略语义进行并行化处理。
swap
交换
clear
清空
```c++ void clear() noexcept; ```
```c++ void clear() noexcept; ```
Erases all elements in the table.
清空容器中的所有元素。
Postconditions:;; `size() == 0`, `max_load() >= max_load_factor() * bucket_count()` Concurrency:;; Blocking on `*this`.
后置条件：容器大小 `size() == 0`，且 `max_load() &gt;= max_load_factor() * bucket_count()`
并发：会阻塞当前对象 `*this`。
Returns:;; The number of elements inserted. Concurrency:;; Blocking on `*this` and `source`.
返回值：插入的元素数量。
并发：会阻塞当前对象 `*this` 和源对象 `source`。
Observers
观察器
get_allocator
get_allocator
A binary function object that induces an equivalence relation on values of type `Key`. It takes two arguments of type `Key` and returns a value of type `bool`.
一种二元函数对象，用于在Key类型的值上引入等价关系。该对象接收两个Key类型的参数，并返回一个bool类型的值。
_Allocator_
_Allocator_
An allocator whose value type is the same as the table's value type.
值类型与哈希表值类型相同的分配器。

Loading…

User avatar admin

Translation uploaded
Erases the element with key equivalent to `k` if it exists.
Erases the element with key equivalent to `k` if it exists.若存在键等价于`k`的元素，则删除该元素。
06/05/2026
User avatar admin

String added in the repository
Erases the element with key equivalent to `k` if it exists.
Erases the element with key equivalent to `k` if it exists.
06/05/2026
Browse all string changes

Glossary

English Chinese (Simplified Han script)
No related strings found in the glossary.

String information

Flags
safe-html, strict-same
Unit identifier
54023
Source string location
:1412
String age
06/05/2026
Last updated
06/06/2026
Source string age
06/05/2026
Translation file AsciiDoc file
doc/modules/ROOT/pages/reference/concurrent_flat_map_zh_Hans.adoc, string 326