Cool usecase for std::tie()

Until now I only thought of std::tie()as useful for decomposing several return values of a function that is faking multiple return values by using std:tuple:

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bool a; SomeData b;   std:tie(a, b) = get_a_b_as_tuple();

But now look at that:

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structS {   int n;   std::string s;   float d;     bool operator<(const S& rhs) const {     // compares n to rhs.n,     // then s to rhs.s,     // then d to rhs.d     return std::tie(n, s, d) < std::tie(rhs.n, rhs.s, rhs.d);   } };

Nice, isn't it?

Source: CppCon2015 / Presentations / Simple Extensible Pattern Matching With C++14.

Update:
As it seems, this technique is considered to be pretty standard now, look here. If you are interested in TMP (and param pack expansions ;) you'll find there some techniques to make such comparators more flexible.