Tony Hoare answers questions [video] | Hacker News Reader

Tony Hoare answers questions [video]

newton.ac.uk

83 pointstimthorn34 comments

When I applied to do my DPhil at Oxford, Tony Hoare was the Professor of Computing and interviewed me. The hardest question he asked me was... "Where else did you apply to do research?" and I replied "Nowhere".

I never found out if that was a good response or not.

But you got in!

What were his easy questions?

I don't remember very well but I think we might have talked about category theory and how I didn't think it was the approach I wanted to take.

It depends - but most people feel warm and fuzzy committing funds to a candidate if they know that they 'got nowhere else to go'

He interviewed me when I applied in the 1980s. He asked whether I what I thought of Ada which was new at the time. I was quite positive about it which was probably the wrong answer, I didn't get in.

I was excited to hear I was being awarded the “CAR Hoare” prize from the same institution, only to find out it was a measly £200, if we’re doing humble brags

For those who may not know, Tony Hoare invented Quicksort and the concept of null in computing, amongst many other fundamental things.

Also Hoare logic.

Also CSP: https://en.wikipedia.org/wiki/Communicating_sequential_proce...

Also, monitors: https://en.wikipedia.org/wiki/Monitor_%28synchronization%29?...

A collection of his essays was published in book form in 1989 and is freely available to download:

Essays in computing science (1989): https://dl.acm.org/doi/book/10.5555/63445

Essays discuss: Algol, Pascal, programming language design, mathematics in computing, data structures and much more.

It's not the first time I'm seeing a q&a with Hoare. Every time someone asks "but how exactly did you figure out quicksort?". He must have heard that a hundred times by now. He should come up with a fake but catchy story, like the Newton gravity apple :)

Honestly, quicksort seems like a really intuitive way to do sorting, so much so that when I was in school I had to keep remembering that merge sort was the "trickier" way (to me).

Null is garbage and responsible for billions of dollars worth of net loss. I wouldn't list null as one of his achievements.

For people voting me down who don't know any better. Tony agrees with me and even himself calls it a great mistake:

Speaking at a software conference in 2009, Tony Hoare apologized for inventing the null reference:

"I call it my billion-dollar mistake. It was the invention of the null reference in 1965. At that time, I was designing the first comprehensive type system for references in an object oriented language (ALGOL W). My goal was to ensure that all use of references should be absolutely safe, with checking performed automatically by the compiler. But I couldn't resist the temptation to put in a null reference, simply because it was so easy to implement. This has led to innumerable errors, vulnerabilities, and system crashes, which have probably caused a billion dollars of pain and damage in the last forty years."

You would think that a logical statement standing by itself and alone would lead to a logical reaction, but no. People respond to authority not to logic. So instead of listing why null is bad here, I just reference tony himself.

So yeah even Tony wouldn't like null listed there as an achievement.

He did great things — terrible, yes, but great.

He did many great things, most of which were not terrible at all. Null, however, was terrible. Glad to see I get voted up for referencing Tony saying the EXACT same thing I said while I get voted down for saying the EXACT same thing Tony said.

The difference is that you provided a warrant for your claim in the second case, but the first claim was unwarranted (had no support). People voted accordingly.

A claim that is correct is voted down because it has no warrant? A better way is to ask for a warrant rather then voting based off of your gut and assumptions as people are doing now.

People don't like being told they are wrong.

Why don't read most of the threads here. Most claims are unwarranted. People vote based off there gut and whether they agree with it, it has nothing to do with substantiated evidence.

Most people here don't know how bad the concept of null is so they voted based off of that, never knowing that the inventor of null dislikes the concept himself.

Also keep in mind, Tony's claim itself has no evidence. He never lists why null is bad. His claim is unwarranted, but his reputation precedes him. You as others do vote based off of emotion and are unable to admit it.

The OP said Hoare had invented null (which is true), not that it was one of his achievement.

So? I said Tony would not like it listed as an achievement. I never said the OP listed null as an achievement (Which is True).

Let's not get too pedantic. The way I said it obviously implies that the OP listed null as an achievement. Similar to how the OP listing null alongside an achievement can imply it's an achievement.

he said that about null himself (my billion dollar mistake), didn't he?

Literally. He called it his own billion dollar mistake. But if I say the exact same thing. People vote me down. It's an example of human psychology at play here.

People don't vote based off of correctness. They vote based off of emotion. Emotion tells them I don't have the authority to say negative things about Tony. Even though I said nothing negative, Tony agrees with what I said.

afaiu core.async in Clojure and channels in Go are inspired by Communicating Sequential Processes (CSP)

https://swannodette.github.io/2013/07/12/communicating-seque...

https://clojure.org/news/2013/06/28/clojure-clore-async-chan...

https://en.wikipedia.org/wiki/Communicating_sequential_proce...

I love the concept of null in computing so much and for golang channels and the most practical concurrent programming paradigm on earth there is CSP. He is a GOAT of this domain.

What's a GOAT?

Greatest Of All Time

adding some context: used most often in discussion of sports in my experience, e.g. Michael Jordan in Basketball, Wayne Gretzky in Hockey, Babe Ruth in Baseball, etc. Carries connotations not only of being one of the best to ever do it, but also a mythos and aura that influenced/continues to influence others.

GOAT as the OG of his field

GOAT Of All Time

We need something suitably recursive for Hoare.

see https://news.ycombinator.com/item?id=27740366

Null is a pox on all our houses, but nonetheless Hoare is awesome.

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