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Ask HN: Concepts that clicked only years after you first encountered them?

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Re: Ask HN: Concepts that clicked only years after you first encountered them?

#71

Post by ericlewis »

pintxo wrote: post #65
latchkey wrote: post #59

Earlier quoted context omitted.

Always amuses me when I see tests spin up a http server, just to call a function.

What specifically amuses you? Todays http servers may have any number of request altering/enhancing "middleware" calls between the incoming request and the actual business logic/function. How do you ensure that your api works as designed if you only test (pure) business functions? Or do you re-create the middleware chain of functions manually for you test?

technically this would be considered an integration test I think.

Re: Ask HN: Concepts that clicked only years after you first encountered them?

#73

Post by zozbot234 »

rramadass wrote: post #60
harimau777 wrote: post #47

Socialism When I got out of my middle class bubble, made friends with people working multiple jobs and struggling to make ends meet, and experienced a period of financial instability; I began to realize that something wasn't working in our current system. Then I started struggling with burnout and other issues and found that corporations were happy to just replace me. I also found that management wanted programmers t…

>In particular the "social democracy" strains of socialism as opposed to those advocating central planning or anarchist organization. Yes; Most people get hung up on terminology and/or specific interpretations but i am convinced this is the natural order of things for the Human species. The balance without going to extremes is what is important.

> Most people get hung up on terminology and/or specific interpretations

Because terminology matters, and some terms are quite misleading. What some people tend to miss about the "Socialism with Scandinavian Characteristics" that folks claim to like these days is that Scandinavian countries are actually near the very top rankings by economic freedom and lack of excess regulatory burden. I.e. they're actually some of the most free market and capitalist, while applying effective redistribution after the fact (leading to moderately high tax rates). So I don't get why people decry capitalism and free enterprise while praising Scandinavia as "successful" socialism? It makes no sense.

Re: Ask HN: Concepts that clicked only years after you first encountered them?

#74

Post by whacked_new »

I love this as a research topic. Here are a few examples close to me.

1. The nature of variance in regression methods. The first time I heard about "soaking up the variance" in modifying stat models in brain imaging I had no idea what was going on. Then I spent a few years doing brain imaging and modified models to "soak up the variance" differently. Over the few years I came to grok the concept. I had a electrical engineering PhD colleague with an impressive resume who would argue with me about the effects of models. I realized that he knew the textbook stuff (which I didn't), but he didn't actually grok the concepts (which I did).

2. Once in an office was I mystified by hot spots and cold spots of wifi signal. One of my colleagues, a brilliant engineer, then explained to me what might affect the shape of the hot and cold spots, which is why he sits in certain places. I asked him if he had an intuition of how RF fields are distributed and he said yes, so I asked him how. He said, "I used to do a bit of tensor calculus".

Re: Ask HN: Concepts that clicked only years after you first encountered them?

#76

Post by jacobsimon »

gavinray wrote: post #46
everybodyknows wrote: post #14

Earlier quoted context omitted.

> dependency injection The term is unfamiliar to me -- is it related to "fault injection"?

Going to steal a description I wrote for a blogpost several years ago, when I had recently understood DI for the first time so it was very fresh in my mind: https://hasura.io/blog/build-fullstack-apps-nestjs-hasura-gr... Dependency Injection solves the problem of when you want to create something, but THAT something also needs OTHER somethings, and so on. In this example, think about a car. A car might have many sepa…

I think you might have it backwards. The first example _is_ dependency injection, too, since you are passing the required instances into the constructor. The non-DI approach would be for the Car class to import and instantiate the Wheels class inside its constructor function.

Re: Ask HN: Concepts that clicked only years after you first encountered them?

#77

Post by xigoi »

harimau777 wrote: post #47

Socialism When I got out of my middle class bubble, made friends with people working multiple jobs and struggling to make ends meet, and experienced a period of financial instability; I began to realize that something wasn't working in our current system. Then I started struggling with burnout and other issues and found that corporations were happy to just replace me. I also found that management wanted programmers t…

Interesting. Here in Czechia, “socialism” and “social democracy” are two very different things — one is the oppressive regime we had decades ago, the other is the current system that works reasonably well.

Re: Ask HN: Concepts that clicked only years after you first encountered them?

#78

Post by atonse »

rolisz wrote: post #50

Differential equations took a couple of years to grok. I first encountered them in high school, while preparing for physics Olympiad. I could solve basic differential equations by following the "rules" (such as for dampened oscilator), but I didn't understand what was going on under the hood. When in university I did some more math courses, suddenly differential equations clicked and made sense (and I could even deri…

I failed calculus twice in college.

Then a summer went by before the third time I took it.

When I stepped into class that third time, everything clicked and it all felt very obvious to the point where I could anticipate where the lecturer’s equations were headed.

I stopped attending class and still got an A. I even ended up helping classmates in a study group.

I still can’t explain what that brain process was that resulted in the pieces subconsciously lining up over the summer.

Re: Ask HN: Concepts that clicked only years after you first encountered them?

#80

Post by zozbot234 »

xigoi wrote: post #77
harimau777 wrote: post #47

Socialism When I got out of my middle class bubble, made friends with people working multiple jobs and struggling to make ends meet, and experienced a period of financial instability; I began to realize that something wasn't working in our current system. Then I started struggling with burnout and other issues and found that corporations were happy to just replace me. I also found that management wanted programmers t…

Interesting. Here in Czechia, “socialism” and “social democracy” are two very different things — one is the oppressive regime we had decades ago, the other is the current system that works reasonably well.

Czechia is still undergoing catch-up growth, much like Germany during the Wirtschaftswunder (that made their "social market economy" widely popular) and emerging countries today. When people say "social democracy" doesn't work all that well compared to leaner approaches, they mean countries where that growth process has concluded. With an overregulated economy and a high burden of all sorts of excess red tape, they tend to get stuck in a middle-income trap that leads to widespread unhappiness.
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