Hi Ben, as Jens has pointed out, it pays off to read the context of an exercise (like in the real world). The second exercise states
> If the terminology poses any difficulties, do re-read BSL Grammar. where “BSL Grammar” is a link that explains BSL via a data definition (that’s what a grammar is) and explains the terminology of — function application — function definition which are TWO distinct concepts. Sadly, math teachers gloss over this distinctions in school (if they know it) and other teachers do not know it. In computing, especially programming, precise terminology is critical so that you can efficiently communicate with others. After all, programming is a people discipline not a cubicle sport (even if you do sit in a cubicle in many shops; but that’s because of many other problems). So for your sake, I urge you to catch up on Intermezzo I so that you understand these distinctions. Having said that, I will move this sentence (hint) to the preceding exercise so that others don’t get hung up on this terminology issue. — Matthias p.s. This explanation does probably not apply to people who just wish to learn to code and remain cheap rent-a-coders. But that’s a path they should choose after experiencing this fate for a couple of years in a company. > On Jul 12, 2017, at 10:58 PM, Ben Morin <benand...@gmail.com> wrote: > > Hi Jens > > Thanks for the reply. > > I was working through it with some free time today, and I think my data > definition works. The other big problem I was having was the body for the > user-defined function. As you said, ex 356 isn't concerned about that aspect. > This is what was/is throwing me off. My assumption is now that I would define > the body of an arbitrary function in the arguments of eval-definition1. > > For instance: > > (eval-definition1 '(by-five (make-add 1 1)) 'by-five 'p (make-mul 5 'p)) > > The first arg being the expression to evaluate. > Second is the function name being evaluated for. > Third being 'by-five's parameter. > Fourth being the actual body of 'by-five. > > The result of eval-definition1 then being 10. > > I hope this is heading in the right direction. > > -- > You received this message because you are subscribed to the Google Groups > "Racket Users" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to racket-users+unsubscr...@googlegroups.com. > For more options, visit https://groups.google.com/d/optout. -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to racket-users+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
