[fsloth]

What a beautiful example of abuse of C++ templates. I love it.

But please don’t do this in production.

What ever you need to do, use C++ templates as the last resort because you’ve figured out all other approaches suck even more. Maintaining template heavy code is absolutely horrible and wasteful (and if it’s C++ production code we measure it’s lifetime in decades). And no, there is no way ”to do it correctly so it doesn’t suck”.

Templates belong to the lowest abstraction levels - as stl mostly does. Anyhting more prevalent is an abomination.

If the schema is fixed, have types with the data and if you have a default data, provide it using initializer lists.

Ie. have a struct or structs with explicit serializeToJson and deserializeFromJson functions.

It’s faster to write than figuring out the correct template gymnastics and about 100x easier to maintain and extend.

[qsdf38100]

This reminds me of some coworkers I had that moaned anytime they saw 'template' in some code. They were convinced that templates were just bad, and that they should stay in the STL. Some of these people would then proceed to use void* and enums to perform the same computations (the C++ haters kind), or use virtual functions all over the place (the java-background kind). Not only was the result much more fragile (compile errors are now runtime errors), but it would also prevent inlining, not to mention the dynamic memory allocation fest.

[fsloth]

No, don’t abuse the language.

Wrap everything in types and all is fine.

Verbose C++ is the only good kind of C++. Why?

C++ code needs to be debuggable and modifiable so when a profiler shows hotspots, you know where they are coming from and react appropriately.

How do you fix a hotspot on a one line of code somewhere in the middle of a template thingsmajic?

You don’t. You need to unroll the template code to untemplated code and the fix the hotspot.

Cases where you don’t need to fix one line hotspots because the resources consumed by the code are irrelevant are fine. But if performance does not matter it likely means you should use a bette language than C++.

Using C++ and not caring about performance finetuning is the worst of both worlds - you are using a cumbersome language AND it’s not even for any practical benefit.