Why were FEXPRs abandoned in Common Lisp? -

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many lisps had fexprs not included in cl.
read because fexrps don't work static analysis.
can explain this?

from wikipedia article on fexprs:

at 1980 conference on lisp , functional programming, kent pitman presented paper "special forms in lisp" in discussed advantages , disadvantages of macros , fexprs, , condemned fexprs. central objection that, in lisp dialect allows fexprs, static analysis cannot determine whether operator represents ordinary function or fexpr — therefore, static analysis cannot determine whether or not operands evaluated. in particular, compiler cannot tell whether subexpression can safely optimized, since subexpression might treated unevaluated data @ run-time.


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