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Difference between revisions of "cpp/string/basic string view/hash"

From cppreference.com
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{{dcl header | string_view}}
 
{{dcl header | string_view}}
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template<> struct hash<std::string_view>;
 
template<> struct hash<std::string_view>;
 
template<> struct hash<std::wstring_view>;
 
template<> struct hash<std::wstring_view>;
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Template specializations of {{lc|std::hash}} for the various view classes for hashing views.
 
Template specializations of {{lc|std::hash}} for the various view classes for hashing views.
  
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These hashes equal the hashes of corresponding {{lc|std::basic_string}} classes: If S is one of the standard basic_string types, SV is the corresponding string view type, and s is an object of type S, then {{c|std::hash<S>()(s) {{==}} std::hash<SV>()(SV(s))}}.
 
These hashes equal the hashes of corresponding {{lc|std::basic_string}} classes: If S is one of the standard basic_string types, SV is the corresponding string view type, and s is an object of type S, then {{c|std::hash<S>()(s) {{==}} std::hash<SV>()(SV(s))}}.
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===See also===
 
===See also===
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[[zh:cpp/string/basic_string_view/hash]]
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Revision as of 09:34, 14 April 2018

 
C++
 
Strings library
 
std::basic_string_view
 
Defined in header <string_view>
template<> struct hash<std::string_view>;

template<> struct hash<std::wstring_view>;
template<> struct hash<std::u16string_view>;

template<> struct hash<std::u32string_view>;
 (since C++17)

Template specializations of std::hash for the various view classes for hashing views.

These hashes equal the hashes of corresponding std::basic_string classes: If S is one of the standard basic_string types, SV is the corresponding string view type, and s is an object of type S, then std::hash<S>()(s) == std::hash<SV>()(SV(s)).

See also

(C++11)
 hash function object
(class template) [edit]
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