rtti

I understand that there is a resource hit from using RTTI, but how big is it? Everywhere I've looked just says that "RTTI is expensive," but none of them actually give any benchmarks or quantitative data reguarding memory, processor time, or speed. So, just how expensive is RTTI? I might use it on an embedded system where I have only 4MB of RAM, so every bit counts. Edit: As per S. Lott's answer , it would be better if I include what I'm actually doing. I am using a class to pass in data of different lengths and that can perform different actions , so it would be difficult to do this using

How come when I run this main.cpp : #include <iostream> #include <typeinfo> using namespace std; struct Blah {}; int main() { cout << typeid(Blah).name() << endl; return 0; } By compiling it with GCC version 4.4.4: g++ main.cpp I get this: 4Blah On Visual C++ 2008, I would get: struct Blah Is there a way to make it just print Blah or struct Blah ? The return of name is implementation defined : an implementation is not even required to return different strings for different types. What you get from g++ is a decorated name , that you can "demangle" using the c++filt command or __cxa_demangle .

I have declared the following enum type in which I want the first member to have the ordinal value of 1 (one) rather than the usual 0 (zero): type TMyEnum = ( meFirstValue = 1, meSecondValue, meThirdValue ); If I call TypeInfo() , e.g. as part of a call to GetEnumName() , I get a compiler error: GetEnumName(TypeInfo(TMyEnum), Ord(aValue)); ERROR: "E2134: Type 'TMyEnum' has no typeinfo" Why is this? I know that classes only have typeinfo if they are compiled with the $M compiler option enabled or (derive from some class which was, such as TPersistent ) but I didn't think there were any special