C++ Setting std::tuple values in an std::unordered_map

Question

I have an unordered map with string keys and a tuple of three strings and one int. How can I access the individual tuples to set them.

Given:

std::unordered_map<string,std::tuple<string, string, string,int>> foo_data_by_username;

How can I set the individual tuple values of say foo_data_by_username[some_user];

Beware that using tuples can infect your code with magic numbers (std::get<0> -- what is "0" supposed to mean)? You might be better off using a custom POD type so that you can give each piece of data a useful name, as well as the ability to add/remove members without having to adjust tuple indices everywhere in your code. — cdhowie
– cdhowie, Commented Apr 3, 2017 at 17:09

Brian Rodriguez · Accepted Answer · 2017-04-03 17:07:04Z

6

std::get<0>(foo_data_by_username[some_user]) = "new string";

Where 0 is whichever index of the tuple you're interested in.

answered Apr 3, 2017 at 17:07

Brian Rodriguez

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