4 ms·

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

MaxBarraclough 5y ago
Also Hoare logic.
- xfer 5y ago
  Also CSP: https://en.wikipedia.org/wiki/Communicating_sequential_processes https://en.wikipedia.org/wiki/Communicating_sequential_proce...
  - lou1306 5y ago
    Also, monitors: https://en.wikipedia.org/wiki/Monitor_%28synchronization%29?wprov=sfla1 https://en.wikipedia.org/wiki/Monitor_%28synchronization%29?...
open-source-ux 5y ago
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 https://dl.acm.org/doi/book/10.5555/63445 Essays discuss: Algol, Pascal, programming language design, mathematics in computing, data structures and much more.
H8crilA 5y ago
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 :)
- cbsmith 5y ago
  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).
shadowlight 5y ago
Null is garbage and responsible for billions of dollars worth of net loss. I wouldn't list null as one of his achievements.
- shadowlight 5y ago
  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.
  - hyperpallium2 5y ago
    He did great things — terrible, yes, but great.
    - shadowlight 5y ago
      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.
      - tuatoru 5y ago
        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.

MaxBarraclough 5y ago

Also Hoare logic.

xfer 5y ago
Also CSP: https://en.wikipedia.org/wiki/Communicating_sequential_processes https://en.wikipedia.org/wiki/Communicating_sequential_proce...
- lou1306 5y ago
  Also, monitors: https://en.wikipedia.org/wiki/Monitor_%28synchronization%29?wprov=sfla1 https://en.wikipedia.org/wiki/Monitor_%28synchronization%29?...

open-source-ux 5y ago

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 https://dl.acm.org/doi/book/10.5555/63445 Essays discuss: Algol, Pascal, programming language design, mathematics in computing, data structures and much more.

H8crilA 5y ago

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 :)

cbsmith 5y ago
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).

shadowlight 5y ago

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

shadowlight 5y ago
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.
- hyperpallium2 5y ago
  He did great things — terrible, yes, but great.
  - shadowlight 5y ago
    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.
    - tuatoru 5y ago
      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.