"(It's not clear to me that it has any use at all if you don't have higher-order functions.)" It can be done. There are plenty of C codebases that end up havin

"(It's not clear to me that it has any use at all if you don't have higher-order functions.)" It can be done. There are plenty of C codebases that end up having something defunctionalized eventually. It's arguably one of the main pressures that causes Greenspun's 10th Rule [1] to be so accurate; as your codebase grows the odds that you'll be forced to defunctionalize something significant in your code goes to 100%. It isn't any fun, though. [1]: "Any sufficiently complicated C or Fortran program contains an ad hoc, informally-specified, bug-ridden, slow implementation of half of Common Lisp."