std::basic_string_view<CharT,Traits>:: find
From cppreference.com
<
cpp
|
string
|
basic string view
|
constexpr
size_type find
(
basic_string_view v, size_type pos
=
0
)
const
noexcept
;
|
(1) | (since C++17) |
|
constexpr
size_type find
(
CharT ch, size_type pos
=
0
)
const
noexcept
;
|
(2) | (since C++17) |
|
constexpr
size_type find
(
const
CharT
*
s, size_type pos, size_type count
)
const
;
|
(3) | (since C++17) |
|
constexpr
size_type find
(
const
CharT
*
s, size_type pos
=
0
)
const
;
|
(4) | (since C++17) |
Finds the first substring equal to the given character sequence.
1)
Finds the first occurence of
v
in this view, starting at position
pos
.
2)
Equivalent to
find
(
basic_string_view
(
std::
addressof
(
ch
)
,
1
)
, pos
)
.
3)
Equivalent to
find
(
basic_string_view
(
s, count
)
, pos
)
.
4)
Equivalent to
find
(
basic_string_view
(
s
)
, pos
)
.
Parameters
| v | - | view to search for |
| pos | - | position at which to start the search |
| count | - | length of substring to search for |
| s | - | pointer to a character string to search for |
| ch | - | character to search for |
Return value
Position of the first character of the found substring, or npos if no such substring is found.
Complexity
O( size() * v. size() ) at worst.
Example
Run this code
#include <string_view> int main() { using namespace std::literals; constexpr auto str{" long long int;"sv}; static_assert( 1 == str.find("long"sv) && "<- find(v , pos = 0)" && 6 == str.find("long"sv, 2) && "<- find(v , pos = 2)" && 0 == str.find(' ') && "<- find(ch, pos = 0)" && 2 == str.find('o', 1) && "<- find(ch, pos = 1)" && 2 == str.find("on") && "<- find(s , pos = 0)" && 6 == str.find("long double", 5, 4) && "<- find(s , pos = 5, count = 4)" ); static_assert(str.npos == str.find("float")); }
See also
|
find the last occurrence of a substring
(public member function) |
|
|
find first occurrence of characters
(public member function) |
|
|
find last occurrence of characters
(public member function) |
|
|
find first absence of characters
(public member function) |
|
|
find last absence of characters
(public member function) |
|
|
finds the first occurrence of the given substring
(public member function of
std::basic_string<CharT,Traits,Allocator>
)
|