2411: Instead of digging through nested spoilers, you just click "Quote".
2412: You use the "Modify" button instead 

Quigibo, thanks for explaining Lambdas to me. I can really see how they might be used now.

Anyway, yeongJIN_COOL, while the others are right, I do remember wanting to learn SMC for myself. I still maintain that you don't need it for your current project. There's very little good information available on it because it's such a difficult/specialized technique*. The basic situation where SMC is used is those cases where you have code that is largely repetitive. It occasionally turns out that it's actually more efficient to write new code in where the old code differs than to use two different blocks of code. The whole thing hinges on the fact that code and data are exactly the same thing at the machine level. When you write to memory, you're potentially writing valid code, even if it will never be executed.

The basic cycle of SMC is

1: Execute
2: Write new code to the existing code in (1)
3: Goto (1)

Now, SMC is very dangerous because if you set a single bit in the code improperly, you may cause a complete program crash and also because it can be very difficult to follow the flow of a self modifying program, leading to bugs if you're not careful.

Basically, avoid SMC like the plague unless there's some problem that cannot be reasonably solved without it or you have near-complete access to/understanding of the assembly level source. When you have to use it, spend a lot of time making sure that the SMC is *absolutely* correct before writing anything else. Bad SMC can have some incredibly strange behavior.

* I spent quite awhile on Google reading comments about how "you shouldn't use SMC" before I gave up and asked Calc84. Now I use it in Khavi to solve the difficult problem of not knowing where in memory the interpreter threads will be located at any time before runtime. Windows uses a very similar method to get programs to run at places in memory that they weren't compiled to run at.

question lists
1: How does it work?
2:How do I use it?
3: Can I see the example(code) of it?

1) Code that modifies itself while it's running is called "Self-modifying code."

2) You modify the code, then you change PC to point to the modified code. However, there are very few situations in which SMC is the only way to write a program. I would highly recommend avoiding it if at all possible, especially if you're working with Axe rather than ASM.

3) Cue calc84...

Yeah. lobsters are great(to eat). we would never mistreat them
Anyways, what are they going to do next? sue us for mistreatment of fish?

Holy Necropost, Batman 

That's mostly because I don't like using .s files. Everything except the Gnu GPL is still source, though.

Yes.

:cos(A)->D
:sin(A)->E
:For(X,0,95)
:For(Y,0,63)
:If pxl-Test(X,Y)^r
:Pxl-on(X-Y*E//128,Y8D+(X-16*E)//128)
:END:END:END
That's a bit more optimized, although I'm sure Runer could improve upon it.