[thowawayburnout]

I have found while the C++ error messes can be very long, its surprisingly often in the first line of the error message that you see the problem.

[pjmlp]

Also since clang, at least using recent versions of clang, gcc and VC++ they use heuristics to try to present some kind of meaningful message.

And latest C++14 and C++17 changes also help library writers to error check the type parameters.

Of course those that have to use other compilers still need to face the sea of incomprehensible error messages.

And in any case, better stay away from template meta-programming libraries, at least until modules and concepts eventually land.