alt Hacker NewsSounds genuinely horrible to program this way.
> A Lisp programmer does not need to …
Have you even seen R? Jupyter notebooks? The above sounds like a level of insanity beyond that.
The problem with checking things at runtime is that it’s an ever-moving target. Changed this? Now that other thing is out of sync. Changed that? Now the first thing is gone, and it came from far away so you can’t get it back in this session.
Most lisp systems get recompiled from sources, and while they support dumping an image, that's essentially an optimization. Emacs for example makes an initial dump, then loads the rest from .el files, and the base image remains static (you can dump a new image from a running emacs, but it's always been fiddly). The only thing left that I know of that's image-first is Smalltalk, and not even all implementations.