“Mostly functional” programming does not work

Post by [deleted] » Tue, Apr 29, 2014, 6:30 PM UTC

orbifold wrote: post #178

marcosdumay wrote: post #117

Earlier quoted context omitted.

Now that I've read your post, I'd say that impurity is much more similar to "goto" than with object orientation. A language with "goto" is not structured. It does not matter how often it's used, or how similar the rest of the language is to a structured one. The same is true for side effects. (Funny thing that the most used language has both.)

If code is structured or not is not really a property of a language, every function call is effectively a "goto" although with more convenient syntax. If your functions are partitioned in a strange way, you can just as easily produce spaghetti code. Same with nested if statements. You can write well structured code in Fortran 77 for example, even though most standard control structures involve a goto. Absence of a go…

Post by [deleted] » Tue, Apr 29, 2014, 6:31 PM UTC

orbifold wrote: post #178

marcosdumay wrote: post #117

Earlier quoted context omitted.

Now that I've read your post, I'd say that impurity is much more similar to "goto" than with object orientation. A language with "goto" is not structured. It does not matter how often it's used, or how similar the rest of the language is to a structured one. The same is true for side effects. (Funny thing that the most used language has both.)

If code is structured or not is not really a property of a language, every function call is effectively a "goto" although with more convenient syntax. If your functions are partitioned in a strange way, you can just as easily produce spaghetti code. Same with nested if statements. You can write well structured code in Fortran 77 for example, even though most standard control structures involve a goto. Absence of a go…

Post by lomnakkus » Tue, Apr 29, 2014, 8:40 PM UTC

taeric wrote: post #194

lomnakkus wrote: post #190

Earlier quoted context omitted.

Any kind of static typing (regardless of how primitive) is compiler assistance. Do you think that all static typing is worthless?

I'm not sure how that even follows from what I wrote. Note, I am all for extensive static analysis. To the point that I am excited about such tools as Coverity and friends. I am beginning to take exception to requiring ever more from the programmer. To the point that a programmer can't "in practice" specify a program correctly without a type checker. (Which... is what the parent post says. Right?) I would much rather…

Post by dllthomas » Tue, Apr 29, 2014, 11:16 PM UTC

angersock wrote: post #155

dllthomas wrote: post #136

Earlier quoted context omitted.

There is an element of truth to this. It is also how we get things like Heartbleed.

So, library code and critical infrastructure would fall outside of the "vast majority of cases". :) And again, the question there is "Did Heartbleed keep people from getting value out of OpenSSL?". The answer is no, even if the value provided wasn't as advertised. It was more useful to have something--anything!--than nothing.

Post by yohanatan » Wed, Apr 30, 2014, 6:48 AM UTC

danenania wrote: post #84

yason wrote: post #54

I think that "Mostly functional" is actually the sweet spot. Going to any extreme makes some things horribly difficult and going to another does the same for other things. So, optimally, multiple paradigms coexist in the single codebase, applied where they're most useful. Functional programming with as many immutable bits as possible is definitely a good start. I generally do that for whatever problem I'm solving: I…

I agree with you in general about 'mostly functional' being a sweet spot, but I think there's also lots of room for pure functions and immutability in ui programming without bending over backward too much. For example, rather than creating a big oo hierarchy to model a ui, you can describe it declaratively as immutable data, then transform it with chains of pure and semi-pure functions whose only ultimate side effect…