[string.replace]

# 27 Strings library [[strings]](./#strings)

## 27.4 String classes [[string.classes]](string.classes#string.replace)

### 27.4.3 Class template basic_string [[basic.string]](basic.string#string.replace)

#### 27.4.3.7 Modifiers [[string.modifiers]](string.modifiers#string.replace)

#### 27.4.3.7.6 basic_string​::​replace [string.replace]

[🔗](#lib:replace,basic_string)

`constexpr basic_string& replace(size_type pos1, size_type n1, const basic_string& str);
`

[1](#1)

[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/strings.tex#L3965)

*Effects*: Equivalent to: return replace(pos1, n1, str.data(), str.size());

[🔗](#lib:replace,basic_string_)

`constexpr basic_string& replace(size_type pos1, size_type n1, const basic_string& str,
                                size_type pos2, size_type n2 = npos);
`

[2](#2)

[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/strings.tex#L3977)

*Effects*: Equivalent to:return replace(pos1, n1, basic_string_view<charT, traits>(str).substr(pos2, n2));

[🔗](#lib:replace,basic_string__)

`template<class T>
  constexpr basic_string& replace(size_type pos1, size_type n1, const T& t);
`

[3](#3)

[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/strings.tex#L3992)

*Constraints*: 

- [(3.1)](#3.1)

is_convertible_v<const T&, basic_string_view<charT, traits>> istrue and

- [(3.2)](#3.2)

is_convertible_v<const T&, const charT*> isfalse[.](#3.sentence-1)

[4](#4)

[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/strings.tex#L4003)

*Effects*: Equivalent to:basic_string_view<charT, traits> sv = t;return replace(pos1, n1, sv.data(), sv.size());

[🔗](#lib:replace,basic_string___)

`template<class T>
  constexpr basic_string& replace(size_type pos1, size_type n1, const T& t,
                                  size_type pos2, size_type n2 = npos);
`

[5](#5)

[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/strings.tex#L4020)

*Constraints*: 

- [(5.1)](#5.1)

is_convertible_v<const T&, basic_string_view<charT, traits>> istrue and

- [(5.2)](#5.2)

is_convertible_v<const T&, const charT*> isfalse[.](#5.sentence-1)

[6](#6)

[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/strings.tex#L4031)

*Effects*: Equivalent to:basic_string_view<charT, traits> sv = t;return replace(pos1, n1, sv.substr(pos2, n2));

[🔗](#lib:replace,basic_string____)

`constexpr basic_string& replace(size_type pos1, size_type n1, const charT* s, size_type n2);
`

[7](#7)

[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/strings.tex#L4046)

*Preconditions*: [s, s + n2) is a valid range[.](#7.sentence-1)

[8](#8)

[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/strings.tex#L4050)

*Effects*: Determines the effective length xlen of the string to be
removed as the smaller of n1 and size() - pos1[.](#8.sentence-1)

Ifsize() - xlen >= max_size() - n2 throws length_error[.](#8.sentence-2)

Otherwise,
the function replaces the characters in the range
[begin() + pos1, begin() + pos1 + xlen)
with a copy of the range [s, s + n2)[.](#8.sentence-3)

[9](#9)

[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/strings.tex#L4059)

*Returns*: *this[.](#9.sentence-1)

[10](#10)

[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/strings.tex#L4063)

*Throws*: 

- [(10.1)](#10.1)

out_of_range if pos1 > size(),

- [(10.2)](#10.2)

length_error if the length of the resulting string
would exceed max_size(), or

- [(10.3)](#10.3)

any exceptions thrown by allocator_traits<Allocator>​::​allocate[.](#10.sentence-1)

[🔗](#lib:replace,basic_string_____)

`constexpr basic_string& replace(size_type pos, size_type n, const charT* s);
`

[11](#11)

[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/strings.tex#L4079)

*Effects*: Equivalent to: return replace(pos, n, s, traits​::​length(s));

[🔗](#lib:replace,basic_string______)

`constexpr basic_string& replace(size_type pos1, size_type n1, size_type n2, charT c);
`

[12](#12)

[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/strings.tex#L4090)

*Effects*: Determines the effective length xlen of the string to be
removed as the smaller of n1 and size() - pos1[.](#12.sentence-1)

Ifsize() - xlen >= max_size() - n2 throws length_error[.](#12.sentence-2)

Otherwise,
the function replaces the characters in the range
[begin() + pos1, begin() + pos1 + xlen)
with n2 copies of c[.](#12.sentence-3)

[13](#13)

[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/strings.tex#L4099)

*Returns*: *this[.](#13.sentence-1)

[14](#14)

[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/strings.tex#L4103)

*Throws*: 

- [(14.1)](#14.1)

out_of_range if pos1 > size(),

- [(14.2)](#14.2)

length_error if the length of the resulting string
would exceed max_size(), or

- [(14.3)](#14.3)

any exceptions thrown by allocator_traits<Allocator>​::​allocate.

[🔗](#lib:replace,basic_string_______)

`constexpr basic_string& replace(const_iterator i1, const_iterator i2, const basic_string& str);
`

[15](#15)

[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/strings.tex#L4119)

*Effects*: Equivalent to: return replace(i1, i2, basic_string_view<charT, traits>(str));

[🔗](#lib:replace,basic_string________)

`template<class T>
  constexpr basic_string& replace(const_iterator i1, const_iterator i2, const T& t);
`

[16](#16)

[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/strings.tex#L4131)

*Constraints*: 

- [(16.1)](#16.1)

is_convertible_v<const T&, basic_string_view<charT, traits>> istrue and

- [(16.2)](#16.2)

is_convertible_v<const T&, const charT*> isfalse[.](#16.sentence-1)

[17](#17)

[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/strings.tex#L4142)

*Preconditions*: [begin(), i1) and [i1, i2) are valid ranges[.](#17.sentence-1)

[18](#18)

[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/strings.tex#L4146)

*Effects*: Equivalent to:basic_string_view<charT, traits> sv = t;return replace(i1 - begin(), i2 - i1, sv.data(), sv.size());

[🔗](#lib:replace,basic_string_________)

`constexpr basic_string& replace(const_iterator i1, const_iterator i2, const charT* s, size_type n);
`

[19](#19)

[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/strings.tex#L4161)

*Effects*: Equivalent to: return replace(i1, i2, basic_string_view<charT, traits>(s, n));

[🔗](#lib:replace,basic_string__________)

`constexpr basic_string& replace(const_iterator i1, const_iterator i2, const charT* s);
`

[20](#20)

[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/strings.tex#L4172)

*Effects*: Equivalent to: return replace(i1, i2, basic_string_view<charT, traits>(s));

[🔗](#lib:replace,basic_string___________)

`constexpr basic_string& replace(const_iterator i1, const_iterator i2, size_type n, charT c);
`

[21](#21)

[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/strings.tex#L4183)

*Preconditions*: [begin(), i1) and [i1, i2) are valid ranges[.](#21.sentence-1)

[22](#22)

[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/strings.tex#L4187)

*Effects*: Equivalent to: return replace(i1 - begin(), i2 - i1, n, c);

[🔗](#lib:replace,basic_string____________)

`template<class InputIterator>
  constexpr basic_string& replace(const_iterator i1, const_iterator i2,
                                  InputIterator j1, InputIterator j2);
`

[23](#23)

[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/strings.tex#L4200)

*Constraints*: InputIterator is a type that qualifies as an input
iterator ([[container.reqmts]](container.reqmts "23.2.2.2 Container requirements"))[.](#23.sentence-1)

[24](#24)

[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/strings.tex#L4205)

*Effects*: Equivalent to: return replace(i1, i2, basic_string(j1, j2, get_allocator()));

[🔗](#lib:replace_with_range,basic_string)

`template<[container-compatible-range](container.intro.reqmts#concept:container-compatible-range "23.2.2.1 Introduction [container.intro.reqmts]")<charT> R>
  constexpr basic_string& replace_with_range(const_iterator i1, const_iterator i2, R&& rg);
`

[25](#25)

[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/strings.tex#L4217)

*Effects*: Equivalent to:return replace(i1, i2, basic_string(from_range, std::forward<R>(rg), get_allocator()));

[🔗](#lib:replace,basic_string_____________)

`constexpr basic_string& replace(const_iterator i1, const_iterator i2, initializer_list<charT> il);
`

[26](#26)

[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/strings.tex#L4231)

*Effects*: Equivalent to: return replace(i1, i2, il.begin(), il.size());