Parantheses and learners - experience with 14-18 year olds I have just finished giving a two week intensive course to 14-18 year olds at the Mathematics Village near Ephesus in Turkey
The course is based on Bootstrapworld Algebra and Reactive. Internet is very poor in the village, so we cannot use the web based WeScheme versiosn of the course(s). We have converted the Pyret language of the Reactive course to Racket for two reasons: (a) A change of syntax between the two halves had proved confusing for students (b) We don't have an offline Pyret, we had found online to be unusable in ptractice with our flaky internet connections and setting up a local server just looked to be too much work. So we have a variety of experience with our 14-18 year olds, Beginners Language Racket, Pyret, #lang racket with structs. Do we have parenthesis problems? Yes. Worse for students with previous programming experience. We solved them by educating our students in the clues given by drRacket - colouring matching parenthesis. But the most useful trick we taught is to select the whole function and use tab to autoformat it. This immediately makes parenthesis errors obvious. Make of that what you will. Does that mean that an indentation based format would be better? I am not sure. We certainly did *not* see any benefit from giving the second week in indentation based Pyret, as we did three years ago. Pyret was a pain. Error messages were not clear and the whole change confused students. Including students who had used Python, because the syntax looked familiar but the underlying language was different - being functional. Other problems? Two language features caused us trouble, being the cause of impenetrable bugs in student code: (a) Implicit begin .. end in function body. I have been writing Scheme for 20 years, and I **didn't know this existed**, always writing begin .. end in the very rare cases it was needed. Beginner Student (imho correctly) treats this as an error. I would be happy if advanced Racket also treated it as an error. You can end up with bizarre results if it is allowed and you don't notice what you have done. It allows, encourages even, paranthesis errors. (b) Conds allowed without else. Even beginner student allows this. It causes bugs. In htdp/universe you can end up with a void universe or a void somewhere in univers. the error emerges a long distance in space and time from the code that causes it. Make else clauses compulsory. That's my two cents worth. On Saturday, August 17, 2019 at 9:11:57 PM UTC+3, Dario Maiocchi wrote: > > HI all, > > I would personally be unhappy if in racketlang2 we would remove the (). I > don't think they represent a real issue. > > Just to share my personal experience a professional programmer. I learned > clojure like 7 months ago and now I'm learning racketlang and I never > felt the () as a barrier. > > best > > Am Freitag, 26. Juli 2019 03:42:14 UTC+2 schrieb Greg Hendershott: >> >> > I've taught the exact same material at the start of a 3rd year CS PL >> > course, and the students there didn't find the syntax as easy as one >> would >> > hope for students with that much CS “experience”. In fact, >> unsurprisingly, >> > many find the syntax as hard as expected for having trained on very >> > different syntaxes (especially when they are unclear about the >> semantics >> > that were attached to those syntaxes). Although the switch to teaching >> the >> > start of the course with literally the same materials, with the >> students >> > knowing that, seems to have reduced resistance substantially >> (presumably >> > they don't want to be seen as complaining about something 1st year >> > humantities students are fine with). >> >> This makes me wonder if some experienced programmers dislike simple >> syntax, not just because it is unfamiliar to them, but also because it >> is too simple to serve as an effective in-group filter. If humanities >> students are comfortable, we must raise the barrier to entry. ;) >> >> >> p.s. I just now stumbled across the Iron Ring obtained from the Ritual >> of the Calling of an Engineer. Probably everyone has heard of this >> except me, but if anyone hasn't: >> >> https://en.wikipedia.org/wiki/Ritual_of_the_Calling_of_an_Engineer >> > -- 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. To view this discussion on the web visit https://groups.google.com/d/msgid/racket-users/614d8a6a-78d4-468f-8941-c93d4b060efe%40googlegroups.com.
