gregfjohnson

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31.
by gregfjohnson 2y ago
We used LwIP for a project some years ago, and found a very nice way to do system testing. The project involved multiple microcontrollers communicating over an internal LAN. They used a small embedded kernel named MicroCOS, with LwIP as th
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by gregfjohnson 2y ago
A person close to me works at a law firm. She was feeling a bit stagnant, so she connected with a recruiter. She got a very solid offer with a significant pay bump. She gave her two weeks' notice to her firm, including appointments
33.
by gregfjohnson 2y ago
I grew up seeing founder mode first-hand. My dad founded Celestron, and he operated just as Paul is describing. At my current company, I see the CEO doing the exact same thing, which gives me great hope. Huge contrast from my previous st
34.
by gregfjohnson 2y ago
I turn 70 tomorrow, and have been programming for about 53 years. Started a new job about six months ago. I immensely enjoy banging out the code every day. It still feels like a guilty pleasure! "Shouldn't I be doing homework
35.
by gregfjohnson 2y ago
Goofing around with the Y combinator, and quines (programs that print themselves): I wanted to see how much a quine written in C could be made to look like lisp-style self application. Worked out pretty well!
36.
Intuition on the Gödel Incompleteness Theorem via the Y Combinator(gregfjohnson.com)
2 points by gregfjohnson 3y ago|0 comments
37.
by gregfjohnson 3y ago
Heard the following joke a while back, seems pertinent: Gaia making a mental note: "Hmm. The jury is definitely out on whether it's a good idea to combine large fore-brains with opposable thumbs.."
38.
by gregfjohnson 3y ago
One additional comment, regarding the "fac1" functional above: >>> fac1 = lambda f: lambda n: ((n > 1) and n * f(n-1) or 1) If you happened to have a function "my_fac" that calculates the factorial fun
39.
by gregfjohnson 3y ago
Here is a way to look at this in concrete terms, using python. An important class of lambda terms are those for which there is no normal form. In computational terms, these are terms that would cause you to go into an infinite loop if you
40.
by gregfjohnson 3y ago
Thoughtful article - thanks. Humorous aside: I recently came across a hilariously named, occasionally useful, related utility: "tac".
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by gregfjohnson 3y ago
Completely agree. Reading another engineer's code recently, which had egregiously bad names, the following thought occurred to me: Writing software is like writing poetry. Finding the words that perfectly capture and express the essen
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by gregfjohnson 3y ago
A new fusion company name Blue Laser Fusion is working on inertial fusion with new laser technology. Does anyone have information on what they are doing, and what the prognosis is for that company's approach?
43.
by gregfjohnson 3y ago
Thanks so much - I was unaware of this clang flag. I just confirmed, it does exactly what I was hoping for! I suggested that this be an optional flag, not the default behavior. I could see using it for unit-test/static-analysis build
44.
by gregfjohnson 3y ago
Here is my favorite example of errors due to overflow: std::vector<int> vec; // test for sorted.. bool sorted = true; for (size_t i = 0; i < vec.size() - 1ULL; ++i) if (vec[i] > vec[i+1]) { sorted = fals
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by gregfjohnson 3y ago
There’s a fantastic book called “An Immense World” by Ed Yong that covers the incredible range of sensory modalities found in nature. One of the chapters goes into depth on bats and sonar.
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by gregfjohnson 3y ago
If I understand correctly, the computational expense of Bitcoin mining is increased periodically to track any improvements in hardware or software. The value of Bitcoin is thus supposed to be tied to some underlying measure of value. We use
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by gregfjohnson 3y ago
Same. I typically define a function "void bp1(){}" in a common utility file, put "bp1();" where I need a breakpoint, and "b bp1" in gdb. Hacky, sure, but really convenient.
48.
by gregfjohnson 3y ago
This thread brings to mind an issue I’ve wondered about: For hard real-time systems, do people use specialized CPU’s and hardware? Caches can introduce hard-to-predict timing issues. I’m sure there are other aspects of modern hardware tha
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by gregfjohnson 3y ago
Great read for the beginning of a new year. Thank you. Humans have the capacity to become deep and wise. This essay is empirical evidence in support of that assertion! It seems, though, that something has to break for this transition to
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by gregfjohnson 3y ago
Merry Christmas all. Thank you for this thread.
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by gregfjohnson 3y ago
Emmanuel Kant reflected deeply on the ontological argument, as did Godel, Decartes, Spinoza, and Plantinga among others. Perhaps a bit of intellectual openness and a touch of humility would benefit the conversation in this thread? The Sta
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by gregfjohnson 3y ago
After much initial resistance, I've become a fan of pair programming. When things are clicking, ideas spark back and forth. Frames collide and interfere, bits of partial insight are exchanged, and you and your partner arrive at a sol
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by gregfjohnson 3y ago
Fascinating observation, thanks. Relevant to your comment but diverging farther from the original post: Coincidentally, I am taking a beginner's Kabbalah course right now. I wonder if some of the writers of scripture actually used s
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by gregfjohnson 3y ago
Everyone has their own way of stumbling through to a breakthrough, where suddenly things that had been confusing and complex suddenly seem clear, beautiful, and intuitive. Here are a couple of thoughts on Godel's incompleteness theorem
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by gregfjohnson 3y ago
Greatly appreciate the suggestions and pointers! (Not sure how HN orders "reply's", but this is in response to other replys to my initial comment.)
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by gregfjohnson 3y ago
Mind. Officially. Blown. Sometimes the coincidental timeliness of things popping up on Hacker News is just weird. u ROCK deepseagirl! I've recently wanted to start building Linux kernels and play with device drivers again. Wanted
57.
by gregfjohnson 3y ago
The “software as theory” idea is helpful - thanks OP. Right now I’m dealing with some devilishly difficult GPU code, and I now understand that I’ve been working to reverse engineer the authors’ theory from their code. With much effort, I
58.
by gregfjohnson 3y ago
This brought to mind a cute way to think about the Foucault Pendulum. The idea is to select a given latitude on Earth, and then imagine a cone that "just fits" that latitude, in the sense that it is tangent to the earth all the wa
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by gregfjohnson 3y ago
In this comment thread there are some lovely reflections on human nature, how it manifests in technology development, etc. I had a thought recently, and this might be a place to share it that others might enjoy. Pair programming is like nu
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by gregfjohnson 3y ago
I just finished a wonderful book that readers of this comment thread may find interesting: "An Immense World: How Animal Senses Reveal the Hidden Realms Around Us" by Ed Yong. The book is a relatively non-technical deep dive int

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