I noticed that in C++ bool is implicitly converted to char. I realize that they're both stored as 1 byte, but they're fundamentally different types. Is there some compiler flag or something I can set to prevent an implicit conversion between the two? char being automatically converted to bool makes sense, but not the other way around.
for example, the following is valid:
char test = true;
I'm using Xcode with C++17
This conversion is mandated by the C++ standard (part of the integral conversions), so it is not possible to disable this conversion and remain a compliant C++ compiler.
It is possible for compilers to offer non-compliant extensions, but for something like this they would probably prefer a warning to going non-compliant. However, I was not able to find a compiler that offers such a warning (see, for example, No warning for implicit cast of bool to floating type).
Still, an answer might exist in the form of non-compiler tools. It looks like clang-tidy includes a check for implicit conversions from bool.
Here's a possible solution based on the comment by @Eljay:
template<typename T, typename U>
T strict(U u)
{
static_assert(std::is_same_v<T, U>);
return u;
}
and then you can use it like this:
char test = strict<char>(true); // error
char test = strict<char>('a'); // ok
Here's a demo.
boolfits in acharbut not the other way around. - cigienchar test = strict<char>(true);will fail to compile. Just need to make thestricttemplate class that disallows anything that not the type. - Eljay