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Understanding Deducing This (Explicit Object Parameters) in C++23 [Part 3]

FlatMapFan
Cache-Friendly Containers
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2y ago · Oct 1, 2023 2:15 PM
#1
C++23 introduces Explicit Object Parameters (colloquially "Deducing This"). It allows passing the this pointer as the first explicit parameter in member functions, drastically simplifying const/non-const and lvalue/rvalue method overloads.
FlatMapFan · Cache-Friendly Containers
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ConstexprKing
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2y ago · Oct 1, 2023 3:57 PM
#2
Instead of writing 4 separate overloads for operator[] (const, non-const, &, &&), you can write a single template method: template <typename Self> auto&& operator[](this Self&& self, size_t idx) { return std::forward<Self>(self).data[idx]; }!
ConstexprKing · C++ Metaprogramming
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LockFreeLarry
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2y ago · Oct 2, 2023 7:57 PM
#3
It also makes implementing the Curiously Recurring Template Pattern (CRTP) trivial without inheriting from template base classes.
LockFreeLarry · Concurrent Systems
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