Further, note that C does not retain any type information into runtime. This means that, even if, hypothetically, there was a type comparison extension, it would only work properly when the types are known at compile time (ie, it wouldn't work to test whether two void * point to the same type of data). As for typeof: First, typeof is a GCC ...

Jul 3, 2012 · Usually, wanting to find the type of a variable in C++ is the wrong question. It tends to be something you carry along from procedural languages like for instance C or Pascal. If you want to code different behaviours depending on type, try to learn about e.g. function overloading and object inheritance. This won't make immediate sense on your ...

Jun 15, 2023 · Assigning an scalar type (arithmetic types and pointer types) to _Bool or bool, if the scalar value is equal to 0 or compares to 0 it will be 0, otherwise the result is 1: _Bool x = 9; 9 is converted to 1 when assigned to x.

Is there any way that I can discover the type of a variable automatically in C, either through some mechanism within the program itself, or--more likely--through a pre-compilation script that uses the compiler's passes up to the point where it has parsed the variables and assigned them their types? I'm looking for general suggestions about this.

The compiler will not protect you from these events, except maybe through a warning that is generated at compile time. Slicing can also occur when a derived type is implicitly converted to a base type (by value). For conversions that can be downright dangerous (e.g., from a base to a derived type), the C++ standard requires an explicit cast.

Use GetType when you want to get the type at execution time. There are rarely any cases to use is as it does a cast and, in most cases, you end up casting the variable anyway. There is a fourth option that you haven't considered (especially if you are going to cast an object to the type you find as well); that is to use as.

Dec 12, 2019 · It's what it says: the expression must have integral or unscoped type. The line and column number points you to the % operation. This is an integer modulo operation, which requires integers. 2.0 is not an integer, and neither is arr[i]. Use std::fmod instead. But you're going to struggle here. Finding "even" floating-point numbers may be tricky ...

Dec 21, 2011 · Here's a file, foo.c, that will be used in the examples: #define VALUE 4 int main() { const int x = VALUE; return 0; } I use gcc and cpp (the C preprocessor) for the examples, but you can probably do this with whatever compiler suite you have, with different flags, of course. Compilation. First, let's compile foo.c with gcc -o foo.c. What happened?

Feb 22, 2013 · I'm trying to play around with my new class lesson in Pointer Arguments, and i want to make the functions senior and everyoneElse take pointer x, yet when I try to call the function with the pointer pAge, it says Error: Type name is not allowed.

Sep 10, 2014 · This increments Flash_ptr by 0x200 elements, but since Flash_ptr is of type unsigned char * then this just translates to an increment of 0x200 bytes. In order to make this part of a loop and check for an upper bound you would do something like this: