Callbacks are imperative, promises are functional • Hacker News Board

Re: Callbacks are imperative, promises are functional

#151

Post by gruseom » Thu, Apr 04, 2013, 6:47 AM UTC

erichocean wrote: post #150

gruseom wrote: post #88

Earlier quoted context omitted.

I'm afraid you've misunderstood that Wikipedia page. It attributes the phrase "first-order functional programming" to authors other than Kay. All it attributes to Kay is the phrase "value rule". Kay's interest in spreadsheets wasn't about functional programming, it was about interactive and dynamic computation. I have a pdf of the 1984 Scientific American article that Wikipedia is quoting from. It does include the ph…

I've already read the Alan Kay article you mentioned (recently, in fact), and that's not what I took away from it. I guess we'll agree to disagree, I don't think someone needs to use the phrase "first-order functional programming" when they give the very definition of it, which is what Wikipedia does: summarize Kay's argument. I do agree the article itself was quite interesting, and certainly ahead of its time.

What's Kay's argument, then? And how does it relate to FP? I'm curious.

I was making a textual point about the Wikipedia article. Its use of the phrase "first-order functional programming" is hyperlinked to http://journals.cambridge.org/action/displayAbstract?aid=727.... It's not citing Alan Kay.

Re: Callbacks are imperative, promises are functional

#152

Post by erichocean » Fri, Apr 05, 2013, 8:08 AM UTC

gruseom wrote: post #151

erichocean wrote: post #150

Earlier quoted context omitted.

I've already read the Alan Kay article you mentioned (recently, in fact), and that's not what I took away from it. I guess we'll agree to disagree, I don't think someone needs to use the phrase "first-order functional programming" when they give the very definition of it, which is what Wikipedia does: summarize Kay's argument. I do agree the article itself was quite interesting, and certainly ahead of its time.

What's Kay's argument, then? And how does it relate to FP? I'm curious. I was making a textual point about the Wikipedia article. Its use of the phrase "first-order functional programming" is hyperlinked to http://journals.cambridge.org/action/displayAbstract?aid=727... . It's not citing Alan Kay.

I guess I wasn't clear, sorry. What Alan Kay meant by the "spreadsheet value rule" and what the phrase "a limited form of first-order functional progamming" means are semantically equivalent; they are the same thing.

I have no idea if Alan Kay ever used the latter phrase, but it was easier to use that phrase here on HN than Alan Kay's made up phrase, which would have be difficult to understand without the content of the article explaining it.

Re: Callbacks are imperative, promises are functional

#153

Post by gruseom » Fri, Apr 05, 2013, 6:30 PM UTC

erichocean wrote: post #152

gruseom wrote: post #151

Earlier quoted context omitted.

What's Kay's argument, then? And how does it relate to FP? I'm curious. I was making a textual point about the Wikipedia article. Its use of the phrase "first-order functional programming" is hyperlinked to http://journals.cambridge.org/action/displayAbstract?aid=727... . It's not citing Alan Kay.

I guess I wasn't clear, sorry. What Alan Kay meant by the "spreadsheet value rule" and what the phrase "a limited form of first-order functional progamming" means are semantically equivalent; they are the same thing. I have no idea if Alan Kay ever used the latter phrase, but it was easier to use that phrase here on HN than Alan Kay's made up phrase, which would have be difficult to understand without the content of…

Ah, gotcha. I agree with you that spreadsheet formulas are a limited form of first-order functional programming. But the memory model with which they are coupled is just as important (I have in mind the grid addressing system and dataflow semantics) and this does not fit as nicely into the FP paradigm. But I'm repeating what I said in other comments.

Re: Callbacks are imperative, promises are functional

#154

Post by erichocean » Sat, Apr 06, 2013, 12:11 AM UTC

gruseom wrote: post #153

erichocean wrote: post #152

Earlier quoted context omitted.

I guess I wasn't clear, sorry. What Alan Kay meant by the "spreadsheet value rule" and what the phrase "a limited form of first-order functional progamming" means are semantically equivalent; they are the same thing. I have no idea if Alan Kay ever used the latter phrase, but it was easier to use that phrase here on HN than Alan Kay's made up phrase, which would have be difficult to understand without the content of…

Ah, gotcha. I agree with you that spreadsheet formulas are a limited form of first-order functional programming. But the memory model with which they are coupled is just as important (I have in mind the grid addressing system and dataflow semantics) and this does not fit as nicely into the FP paradigm. But I'm repeating what I said in other comments.

But the memory model with which they are coupled is just as important (I have in mind the grid addressing system and dataflow semantics)

Totally agree. My startup is using hierarchical grids as our core datatypes for just that reason (we also support Function cells that are used as values).

"Naming" is one of the core problems in computer science, and grids/spreadsheets elegantly solve that problem for many ad hoc use cases, where functional programming (in all its forms) does not.