Eval considered

Using eval is almost always a bad idea. It's a crutch for bad designs, it opens giant security holes in your code, and in practice it's almost never needed to get actual stuff done.

the more mental overhead is involved in writing complex programs

$ ls -lh *

-rw-r--r-- 1 nikita prague 5.2K Dec 08 17:23 how-to-compile.txt
-rw-r--r-- 1 nikita prague 80.9M Jan 30 13:37 program.hs