On Wed, Feb 08, 2017 at 06:37:17PM +0100, pd wrote: > Picolisp curry function does not follow the pattern, its domain is > completely different and also its image. In other words, you call classical > curry passing it a function argument but you call picolisp curry passing it > several arguments to replace certain symbols inside expressions. It's a > different kind of animal ;-)
Right. Actually, it does not necessarily *replace* certain symbols inside expressions. It does so only if you pass "pattern variables", see http://software-lab.de/doc/refP.html#pat? In the normal, general, case, an environment using 'job' is built. This is called a "closure" is in statically binding systems. I did not want to call the PicoLisp 'curry' function a closure, because it returns a *function* while a closure is not a function but the combination of a piece of code with an environmennt (i.e. a 'job' in PicoLisp). > The classical curry in picolisp is what Alex has defined a few emails > before ;-) I never saw a use for the classical curry, so I (ab)used this catchy name :) Can you give an example where it is useful in PicoLisp? > > ((X) '((Y) (+ X Y))) > ... > The reason for this expression being completely useless in picolisp *I > think* is the use of quote as an alias for lambda thus in practise > protecting them from evaluation and binding This is not the reason. Quote and lambda are abselutely equivalent here. You could do (setq lambda quote) and then ((X) (lambda (Y) (+ X Y))) and have the same result, i.e. a function returning ((Y) (+ X Y)), which is a correct, legal PicoLisp function accepting an single parameter Y and returning a sum. The quote (or lambda) is gone immediately when returning this function. It may seem useless to you because PicoLisp uses dynamic binding (X is evaluated when this function *runs*), but you expected static binding (X is bound to the value from the environment when this function is *built*). The latter is done in the 'classiCurry' example in my last mail using the PioLisp 'curry'. ♪♫ Alex -- UNSUBSCRIBE: mailto:picolisp@software-lab.de?subject=Unsubscribe
