"because it's impossible to do with Lisp syntax." The problem is not with Lisp syntax. The problem is with Lisp's semantics, which makes it much more difficult

"because it's impossible to do with Lisp syntax." The problem is not with Lisp syntax. The problem is with Lisp's semantics, which makes it much more difficult (if at all possible) to compile in one pass. Things like closures, conditions or macros are absent in Pascal.