Programming language for self-modifying code?

Question

• I am recently thinking about writing self-modifying programs, I think it may be powerful and fun. So I am currently looking for a language that allows modifying a program's own code easily.
• I read about C# (as a way around) and the ability to compile and execute code in runtime, but that is too painful.
• I am also thinking about assembly. It is easier there to change running code but it is not very powerful (very raw).

Can you suggest a powerful language or feature that supports modifying code in runtime?

Example

This is what I mean by modifying code in runtime:

  Start:   a=10,b=20,c=0;   label1: c=a+b;   ....   label1= c=a*b;   goto label1; 

and may be building a list of instructions:

  code1.add(c=a+b);   code1.add(c=c*(c-1));   code1. execute(); 

Answer 1

Malbolge would be a good place to start. Every instruction is self-modifying, and it's a lot of fun(*) to play with.

(*) Disclaimer: May not actually be fun.