depish/cppdraft_translate
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

Init

Browse Source
This commit is contained in:
Leonov Artur (Depish)
2025-10-25 03:02:53 +03:00
commit 043225d523
3416 changed files with 681196 additions and 0 deletions
Download Patch File Download Diff File Expand all files Collapse all files

210
cppdraft/vector/capacity.md Normal file
View File

@@ -0,0 +1,210 @@
[vector.capacity]
# 23 Containers library [[containers]](./#containers)
## 23.3 Sequence containers [[sequences]](sequences#vector.capacity)
### 23.3.13 Class template vector [[vector]](vector#capacity)
#### 23.3.13.3 Capacity [vector.capacity]
[🔗](#lib:capacity,vector)
`constexpr size_type capacity() const noexcept;
`
[1](#1)
[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/containers.tex#L10118)
*Returns*: The total number of elements that the vector can hold
without requiring reallocation[.](#1.sentence-1)
[2](#2)
[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/containers.tex#L10123)
*Complexity*: Constant time[.](#2.sentence-1)
[🔗](#lib:reserve,vector)
`constexpr void reserve(size_type n);
`
[3](#3)
[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/containers.tex#L10134)
*Preconditions*: T is *Cpp17MoveInsertable* into vector[.](#3.sentence-1)
[4](#4)
[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/containers.tex#L10138)
*Effects*: A directive that informs avector of a planned change in size, so that it can manage the storage allocation accordingly[.](#4.sentence-1)
Afterreserve(),capacity() is greater or equal to the argument ofreserve if reallocation happens; and equal to the previous value ofcapacity() otherwise[.](#4.sentence-2)
Reallocation happens at this point if and only if the current capacity is less than the
argument ofreserve()[.](#4.sentence-3)
If an exception is thrown
other than by the move constructor of a non-*Cpp17CopyInsertable* type,
there are no effects[.](#4.sentence-4)
[5](#5)
[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/containers.tex#L10157)
*Throws*: length_error if n > max_size()[.](#5.sentence-1)[197](#footnote-197 "reserve() uses Allocator​::​allocate() which can throw an appropriate exception.")
[6](#6)
[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/containers.tex#L10166)
*Complexity*: It does not change the size of the sequence and takes at most linear
time in the size of the sequence[.](#6.sentence-1)
[7](#7)
[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/containers.tex#L10171)
*Remarks*: Reallocation invalidates all the references, pointers, and iterators
referring to the elements in the sequence, as well as the past-the-end iterator[.](#7.sentence-1)
[*Note [1](#note-1)*:
If no reallocation happens, they remain valid[.](#7.sentence-2)
— *end note*]
No reallocation shall take place during insertions that happen
after a call to reserve() until an insertion would make the size of the vector
greater than the value of capacity()[.](#7.sentence-3)
[🔗](#lib:shrink_to_fit,vector)
`constexpr void shrink_to_fit();
`
[8](#8)
[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/containers.tex#L10190)
*Preconditions*: T is *Cpp17MoveInsertable* into vector[.](#8.sentence-1)
[9](#9)
[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/containers.tex#L10194)
*Effects*: shrink_to_fit is a non-binding request to reducecapacity() to size()[.](#9.sentence-1)
[*Note [2](#note-2)*:
The request is non-binding to allow latitude for
implementation-specific optimizations[.](#9.sentence-2)
— *end note*]
It does not increase capacity(), but may reduce capacity() by causing reallocation[.](#9.sentence-3)
If an exception is thrown other than by the move constructor
of a non-*Cpp17CopyInsertable* T, there are no effects[.](#9.sentence-4)
[10](#10)
[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/containers.tex#L10207)
*Complexity*: If reallocation happens,
linear in the size of the sequence[.](#10.sentence-1)
[11](#11)
[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/containers.tex#L10212)
*Remarks*: Reallocation invalidates all the references, pointers, and iterators
referring to the elements in the sequence as well as the past-the-end iterator[.](#11.sentence-1)
[*Note [3](#note-3)*:
If no reallocation happens, they remain valid[.](#11.sentence-2)
— *end note*]
[🔗](#lib:swap,vector)
`constexpr void swap(vector& x)
noexcept(allocator_traits<Allocator>::propagate_on_container_swap::value ||
allocator_traits<Allocator>::is_always_equal::value);
`
[12](#12)
[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/containers.tex#L10229)
*Effects*: Exchanges the contents andcapacity() of*this with that of x[.](#12.sentence-1)
[13](#13)
[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/containers.tex#L10237)
*Complexity*: Constant time[.](#13.sentence-1)
[🔗](#lib:resize,vector)
`constexpr void resize(size_type sz);
`
[14](#14)
[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/containers.tex#L10248)
*Preconditions*: T is*Cpp17MoveInsertable* and *Cpp17DefaultInsertable* into vector[.](#14.sentence-1)
[15](#15)
[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/containers.tex#L10253)
*Effects*: If sz < size(), erases the last size() - sz elements
from the sequence[.](#15.sentence-1)
Otherwise,
appends sz - size() default-inserted elements to the sequence[.](#15.sentence-2)
[16](#16)
[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/containers.tex#L10259)
*Remarks*: If an exception is thrown other than by the move constructor of a non-*Cpp17CopyInsertable*T, there are no effects[.](#16.sentence-1)
[🔗](#lib:resize,vector_)
`constexpr void resize(size_type sz, const T& c);
`
[17](#17)
[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/containers.tex#L10271)
*Preconditions*: T is*Cpp17CopyInsertable* into vector[.](#17.sentence-1)
[18](#18)
[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/containers.tex#L10276)
*Effects*: If sz < size(), erases the last size() - sz elements
from the sequence[.](#18.sentence-1)
Otherwise,
appends sz - size() copies of c to the sequence[.](#18.sentence-2)
[19](#19)
[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/containers.tex#L10282)
*Remarks*: If an exception is thrown, there are no effects[.](#19.sentence-1)
[197)](#footnote-197)[197)](#footnoteref-197)
reserve() uses Allocator​::​allocate() which
can throw an appropriate exception[.](#footnote-197.sentence-1)