; Recently, Jeremy Dunn on Newlisp forum expressed desire to use ; the single argument functions in Newlisp in following fashion: ; ; (sin cos 0.5) = (sin (cos 0.5)) ; ; The motivation is well know in Lisp world: avoidance of parentheses. ; I believe that regularity of the Lisp syntax should be preserved ; and that it is better to be consistent, although more verbose. ; ; However, the problem is interesting. ; ; At least two works are already done in Newlisp in that dyrection. Cyril ; Slobin described make-pass macro: ; ; http://slobin.livejournal.com/148287.html ; ; (define-macro (make-pass) ; (doargs (arg) ; (letex ((Old arg) ; (New (sym (append (string arg) "&")))) ; (define-macro (New) ; (Old (eval (args))))))) ; ; (make-pass catch not print) ; ; Here is how it works: ; ; (catch& while (read-line) ; (setq line (current-line)) ; (if (not& empty? line) ; (print& format "%s\n" line) ; (throw 'empty))) ; ; My construct for composition of arbitrary functions ; or fexprs should be mentioned as well. ; ; http://kazimirmajorinc.blogspot.com/2010/02/composition-of-functions-or-macros.html ; ; Its syntax should be: ; ; ((compose sin cos) 0.5) ; ; Needless to say, compose is "in the spirit" of the Lisp, ; but it is syntactically heavier than original (sin (cos 0.5)). ; And Jeremy didn't liked even Cyril's (sin& cos 5). ; ; So, I adapted Cyril's idea to work without that extra &, but ; then it had to work both like sin& and original sin. (println (sin 3)) (println (sin (cos 4))) (println (sin (cos (sin 5)))) ; 0.1411200081 ; -0.6080830096 ; 0.5433319155 (define-macro (make-pass-adapted) (doargs (arg) (constant arg (letex((arg (eval arg))) (lambda-macro() (arg (eval (if (> (length (args)) 1) (args) (first (args)))))))))) (make-pass-adapted sin cos) (println (sin (+ (cos 0) (cos 0) (cos 0)))) (println (sin cos 4)) (println (sin cos sin (+ 2 3))) ; 0.1411200081 ; -0.6080830096 ; 0.5433319155 ; I'll test it whether it works with Cyril's example. (make-pass-adapted catch not print) (catch while (read-line) (setq line (current-line)) (if (not empty? line) (print format "%s\n" line) (throw 'empty))) ; It's really easy, so I had doubt whether it is important enough ; to blog about that, lets say, sinful sin. However, I noticed ; that it is interesting example of the function that is replaced ; with FEXPR. |

### Using (sin cos 0.5) instead of (sin (cos 0.5)) in Newlisp.

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