(for Ryan Fleury's stream) Variant of the X macro that doesn't require undefinition or redefinition of macros.

X_macro_call_by_name.cpp

// Whatever, just example instructions.
#define INSTRUCTION_TYPE_LIST(instruction_type) \
instruction_type(push, sizeof(u32)) \
instruction_type(pop, sizeof(u32)) \
instruction_type(move, sizeof(u32 *) + sizeof(u32 *))

// Examples of usage (I didn't quite catch what the real usage was):
#define instruction_enum_name(name, size) Instruction_Type_ ## name,
#define instr_size(name, size) (size_t)size,

enum Instruction_Type {
INSTRUCTION_TYPE_LIST(instruction_enum_name)
Instruction_Type_count,
};

// Don't need to #undef anything.

size_t InstructionSizes[] = {
INSTRUCTION_TYPE_LIST(instr_size)
};

// Don't need to #undef anything!