> On Jun 30, 2015, at 8:10 AM, Alexey Cherkaev <alexey.cherk...@gmail.com> > wrote: > > Hi Alexander, > > Thanks for your reply: I had something similar in mind (maybe I should check > out math/array). I was just wondering if there was something more Racket-like > (it still feels that SRFI is somewhat 'foreign' hack). And my last question > remains: wouldn't it be beneficial to have such a generalised 'set!' > system-wide? I understand that Racket focusses more on immutable structures, > but there are still vectors and hash-tables which are inherently mutable and > still have their niche.
This style of set! seems like a bad idea to me. Specifically, one of the basic ideas of algebraic languages is that programs are compositional. Specifically, if I write (a (b x) c), then the meaning of this term depends on the meanings of a, (b x), and c. That is, I can combine these three values to get the result. Generalized set! breaks this intuition. Specifically, (set! (aref x 0 1) 13) does not depend on the value of (aref x 0 1). Rather, it pulls apart this term and uses its subterm’s meanings. Put differently, this is lvalues. I know, I know, I sound like a pure-functional snooty-poo. John -- 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.
