Function cells

[David C. Plummer <DCP@SCRC-QUABBIN.ARPA>]

If CAR == #'CAR were a constant (because it was microcoded), posit a
machine that 'compiles' function into microcode and assigns instructions
opcodes for them which further compilations then use.  [Of course this
creates havoc to programming development.]  Now I can't bind function
cells at all unless I happen to use FUNCALL all the time, which might
very well lose some advantages of calling the instruction directly.  On
more realistic machines, some 'functions' are constants and some are
not.  How can one write portable code that would bind function cells?

MIT students are indeed exposed to these ISSUES which are demonstrated
on CONVENTIONAL hardware (68Ks I believe) that does not run Lisp
natively and therefore bypasses the issues for more Lisp-specific
engines.