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Re: Trying to solve how to do a std::unordered_map<std::pair<..., ...>, ...>

From: Giuseppe D'Angelo <giuseppe.dangelo_at_[hidden]>
Date: Mon, 2 Oct 2023 20:27:13 +0200
On 02/10/2023 19:45, Aaron Gray via Std-Discussion wrote:
> size_t hash = 0;
> hash ^= key.first ? std::hash<string>()( key.first->name ) :
> std::hash<void *>()( nullptr );
> hash ^= key.second ? std::hash<string>()( key.second->name ) :
> std::hash<void *>()( nullptr );
> return hash;

Please don't do this; Use Boost.HashCombine or one of the techniques
described by the newer hashing proposals.

My 2 c,
-- 
Giuseppe D'Angelo

Received on 2023-10-02 18:27:16