Embedded scripting languages

What scripting language would you embed to a program? The performance would not be main issue, since the compiled part of the program would worry about that.

The scripting language would call many functions written in C, C++, or whatever lang that can compile C-like functions (so there needs to be some kind of easy to use FFI).

I thought about options here:
- Lua
- Scheme (tinyscheme or whatever)
- Something else?

Now, what would /prog/ use, and why? ("Read SICP" is not a valid answer here)

>>56
Analyzing the AST only gets you so far because you would have to do it at run time in some cases at least. In a lot of cases it would just take longer to do the analysis.

Interned strings are a good start. As a hash key, they don't need hashing and they will never produce collisions. There is voodoo going on with caching too, which I'm still not clear on.