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constexprint compare( basic_string_view v)constnoexcept; | (1) | (since C++17) |
constexprint compare( size_type pos1, size_type count1, basic_string_view v)const; | (2) | (since C++17) |
constexprint compare( size_type pos1, size_type count1, basic_string_view v, size_type pos2, size_type count2)const; | (3) | (since C++17) |
constexprint compare(const CharT* s)const; | (4) | (since C++17) |
constexprint compare( size_type pos1, size_type count1, const CharT* s)const; | (5) | (since C++17) |
constexprint compare( size_type pos1, size_type count1, const CharT* s, size_type count2)const; | (6) | (since C++17) |
Compares two character sequences.
rlen of the sequences to compare is the smaller ofsize() andv.size(). The function compares the two views by callingtraits::compare(data(), v.data(), rlen), and returns a value according to the following table:| Condition | Result | Return value | |
|---|---|---|---|
Traits::compare(data(), v.data(),rlen) < 0 | this isless thanv | <0 | |
Traits::compare(data(), v.data(),rlen) == 0 | size() < v.size() | this isless thanv | <0 |
size() == v.size() | this isequal tov | 0 | |
size() > v.size() | this isgreater thanv | >0 | |
Traits::compare(data(), v.data(),rlen) > 0 | this isgreater thanv | >0 | |
Contents |
| v | - | view to compare |
| s | - | pointer to the character string to compare to |
| count1 | - | number of characters of this view to compare |
| pos1 | - | position of the first character in this view to compare |
| count2 | - | number of characters of the given view to compare |
| pos2 | - | position of the first character of the given view to compare |
Negative value if this view is less than the other character sequence, zero if the both character sequences are equal, positive value if this view is greater than the other character sequence.
1) Linear in the number of characters compared.
#include <string_view> int main(){using std::operator""sv; static_assert("abc"sv.compare("abcd"sv)<0); static_assert("abcd"sv.compare("abc"sv)>0); static_assert("abc"sv.compare("abc"sv)==0); static_assert(""sv.compare(""sv)==0);}
| compares two strings (public member function of std::basic_string<CharT,Traits,Allocator>)[edit] | |
(C++17)(removed in C++20)(removed in C++20)(removed in C++20)(removed in C++20)(removed in C++20)(C++20) | lexicographically compares two string views (function template)[edit] |
