Refrencing script libraries?

[Homicide13]

I know for scripting languages you can generally (read: always) build your own libraries of functions that can then be referenced from other scripts, and I was wondering if it is possible to do this kind of this with the level scripting for the hpl2 engine. I don't really know anything about AngelScript beyond what I've used to script levels with, but I have a list of function declarations that I would like to put into a library and have added to the script function list. Is this possible at all, or am I eternally doomed to copy and paste my list of functions into every script hps file?

Also as a bonus question, is it ok to have script below the "OnStart""OnEnter" and "OnLeave" functions? I remember from way back when when I tried to teach myself some cpp, I remember something about the order which functions are declared being important, but I don't really remember what these rules were exactly, so if someone could refresh my memory and tell me whether or not they apply to my dear hps files (though I assume that they would).