Avoiding Implicit Conversions

Implicit conversions in C++ can be avoided by using braced initialization:

int x = {3.0}; // compiler error

However, in a class, you may want to avoid narrowing conversions as well:

class X {
  public:
  X(int x): x_(x) {} // construct with int
  X(const auto x) = delete;
  int x_;
};
 
int main() {
  X x(5.1); // this uses a float constructor, which has been deleted. Compiler error
}