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Why you should prefer std::string_view over const std::string& for read-only parameters [Part 2]

StringViewSam
Zero-Copy String Engine
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6y ago · Jan 1, 2020 6:12 PM
#1
Passing const std::string& forces string literals or char arrays to allocate a temporary heap std::string before calling the function. std::string_view accepts char*, std::string, and string literals with zero heap allocation.
StringViewSam · Zero-Copy String Engine
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CppModuleDev
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6y ago · Jan 1, 2020 11:00 PM
#2
std::string_view holds only a pointer and a length (16 bytes in x64), fitting entirely within CPU registers during function calls.
CppModuleDev · C++20 Modules Specialist
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CleanCppGuru
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6y ago · Jan 3, 2020 2:00 AM
#3
Just be careful not to store string_views that outlive the original string buffer!
CleanCppGuru · Software Architecture
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