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Small programming tricks

will-keleher.com

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Re: Small programming tricks

#51

Post by lscharen »

metabagel wrote: post #45
winternewt wrote: post #8

Only a few of these are actual programming tricks. The problem with sharing them is that they'll typically seem obvious to you, since you know them. It's difficult to know what is actually unknown to other people, and if you share stuff everybody knows you risk coming off as arrogant. Here's one that I think more people should know: avoid branches. If I can do the same thing without an if statement and even a logical…

In what context can you avoid branches?

Maybe something (contrived) like this providing no-op defaults?

  total = calculateOrderTotal(user.order);
  if (user.isPremiumMember) {
    total = total * 0.9;        // 10% discount
versus

  total = calculateOrderTotal(user.order);
  discount = calculateDiscount(user);  // Returns 0.9 or 1.0
  total = total * discount;

Re: Small programming tricks

#52

Post by cestith »

craftkiller wrote: post #42
cachvico wrote: post #25

Earlier quoted context omitted.

I'm struggling to comprehend how branches can be avoided (or why one would want to, as they are the cornerstone of programming). I can only think how to obfuscate them, which is rarely useful.

Here's an example of removing a branch that was posted to HN a little over a month ago: https://www.greyblake.com/blog/branchless-rust/

That's a really nice example. Thanks.

Re: Small programming tricks

#53

Post by happytoexplain »

winternewt wrote: post #8

Only a few of these are actual programming tricks. The problem with sharing them is that they'll typically seem obvious to you, since you know them. It's difficult to know what is actually unknown to other people, and if you share stuff everybody knows you risk coming off as arrogant. Here's one that I think more people should know: avoid branches. If I can do the same thing without an if statement and even a logical…

>if you share stuff everybody knows you risk coming off as arrogant

I have always felt like my bar for publishing something (even just to internal wikis/channels) is too high due to being overly self-conscious. I think we should try not to validate that feeling by implying that there is a non-negligible number of readers who will think you have a personality flaw because you wrote down your personal collection of tips in a public place, or that those people deserve consideration in the first place.

There is no such thing as "the things everybody knows". There are just too many things. Even a list of basic tips is probably going to contain one thing I didn't know or perhaps forgot. Write-ups like this are where most of my practical knowledge comes from, not RTFM (which I do).

Re: Small programming tricks

#54

Post by jamiejquinn »

metabagel wrote: post #50
craftkiller wrote: post #42

Earlier quoted context omitted.

Here's an example of removing a branch that was posted to HN a little over a month ago: https://www.greyblake.com/blog/branchless-rust/

OK, but the code with the branch is easier to understand.

Generally agree. As with many optimisations, branchless code can easily be less obvious than the branchy equivalent.

Re: Small programming tricks

#55

Post by robby_w_g »

metabagel wrote: post #50
craftkiller wrote: post #42

Earlier quoted context omitted.

Here's an example of removing a branch that was posted to HN a little over a month ago: https://www.greyblake.com/blog/branchless-rust/

OK, but the code with the branch is easier to understand.

Yeah, I don't buy the premise that branchless code is intrinsically easier to understand. Maybe OP's point is that adding unnecessary branches makes code harder to read? But that's generally the case for any unnecessary code.

Re: Small programming tricks

#56

Post by samdixon »

cachvico wrote: post #27

I find myself using ctrl-r less and less as I make sure that anything of value that I work out goes into a Makefile or the app tooling, for me this is the basis of the dev-ops approach to work (make sure everything is scripted, not worked out on the fly).

ctrl+r still great for targeting your make targets :)

Re: Small programming tricks

#57

Post by louthy »

kccqzy wrote: post #38

A lot more tricks can be learned from just watching AI work. Instead of allowing AI to work autonomously, go back to the old days where you manually approve every command the AI runs. Just recently while doing performance optimization work, I found Opus using the `perf` command in ways I didn’t know possible. Just give AI a real task and carefully read what commands are used by the AI to solve the problem; most likel…

> “the old days”

Is this just plain old rage baiting? I literally can’t tell any more.

Re: Small programming tricks

#58

Post by metabagel »

NegativeLatency wrote: post #41
CableNinja wrote: post #30

Earlier quoted context omitted.

I think that "everyday" would be a stretch, but i dont understand why youd think thats annoying, someone took the time to consider helping the rest of the engineering team grow, by posting something useful. I frequently do the same, but not everyday; only when i think its something actually useful/helpful beyond the everyday crap. Most recently, we have had a huge push to use ai (just like everywhere else), ive been…

I think there's a fine line between helping your team grow and the sorta annoying self promotion I've seen people do in overly broad slack channels. One is actually helping and the other is making yourself more visible to mgmt for promotions.

I rather think the opposite. People who share tips and hacks are genuinely trying to help others, while people who hoard information are competing on an individual basis without regard for team.

Re: Small programming tricks

#60

Post by metabagel »

lscharen wrote: post #51
metabagel wrote: post #45

Earlier quoted context omitted.

In what context can you avoid branches?

Maybe something (contrived) like this providing no-op defaults? total = calculateOrderTotal(user.order); if (user.isPremiumMember) { total = total * 0.9; // 10% discount versus total = calculateOrderTotal(user.order); discount = calculateDiscount(user); // Returns 0.9 or 1.0 total = total * discount;

OK, or maybe...

  total = calculateOrderTotal(user.order);
  total = total * user.discount;
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