What is the purpose of commenting out function argument names? [duplicate]

Question

I'm working with this sdk that generates a skeleton plugin project, as in, all the functions required by the host application are there, just not filled.

Initially, all the function definitions are sorta like this:

void Mod1::ModifyObject(TimeValue /*t*/, ModContext& /*mc*/, ObjectState* /*os*/, INode* /*node*/) {}

With the argument names commented out, why is that? As far as I can tell, if I'm not using the arguments, it makes no difference whether the names are there or not.

Answer 1

I guess there are two reasons for this:

• It's deliberate to essentially only implement what's necessary: Function names and their signatures. They don't define any names, so it's up to you to either pick the suggestions or your own (or none at all).

• It's to avoid extra-pedantic compilers complaining about unused variables that are defined as parameters. If you don't need a parameter, it's most efficient to simply drop it (unless you need it in some other implementation, but the compiler won't necessarily know about that). But then again they could also complain about params that are there, but not named (although you could consider that intentionally omitted).

Answer 2

Some compilers will issue a warning about unused named parameters, but not about unused unnamed parameters. GCC is one such compiler, if the -Wunused-parameter option is used, enabled by -Wextra.

The theory behind this is that an unused named parameter is more likely to be a mistake than an unused unnamed parameter. Of course, that theory doesn't apply to all code.