Re: Python and Scheme

namekuseijin escreveu:
namekuseijin escreveu:
Michele Simionato escreveu:
On Apr 23, 6:19 pm, Sam TH <sam...@xxxxxxxxx> wrote:
[samth@punge:~/work/teaching/current] cat tailcall.ss
(import (rnrs))
(let loop ([n 1000]) (if (zero? n) #f (begin (/ 1 (- n 12)) (loop (- n
1)))))
But the best is Larceny:

$/home/micheles/packages/larceny_src/scheme-script tailcall2.ss

no error here (!!???)

This issues an error:
(let loop ((n 1000) (r #f)) (if (zero? n) r (loop (- n
1) (/ 1 (- n 12)))))

I guess the error is just ignored being in the head of begin since it
affects no further computation...

Perhaps it even simply removes the useless computation when compiling
down to native code?...

Damn, should test first before posting: yes, it does seem to simply
remove the useless declaration from the generated native code, because
this consumes the resulted computation and thus issues the error:

(let loop ((n 1000))
(if (zero? n) #f
(begin (display (/ 1 (- n 12)))
(loop (- n 1)))))


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