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Patterns.dev

patterns.dev

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Re: Patterns.dev

#61

Post by viraptor »

TINJ wrote: post #58
socketcluster wrote: post #44

I find that the more senior you become, the less you rely on software design patterns. Juniors often think that learning design patterns is some kind of career hack which will allow them to skip ahead a decade of experience... There is some utility in many design patterns but the problem is that juniors often miss the nuance and the motivation behind the patterns and they tend to misuse them; often creating more comp…

> For example, I've seen people write code which relies heavily on design patterns but then that same code uses an O(n^2) nested loop to find items that are common between two arrays. There is a simple 'pattern' you can use to store the items of the first array in a Set or HashMap and then finding common items is O(n) because Set and HashMap lookups are O(1)... Very useful pattern but I don't believe it has a name. I…

No, dynamic programming is when you split your bigger problem into a smaller one + 1 step to get to your bigger size. Then apply that recursively until you solve the trivial problem at the end and get back the answer for your original problem size.

Re: Patterns.dev

#62

Post by viraptor »

socketcluster wrote: post #44

I find that the more senior you become, the less you rely on software design patterns. Juniors often think that learning design patterns is some kind of career hack which will allow them to skip ahead a decade of experience... There is some utility in many design patterns but the problem is that juniors often miss the nuance and the motivation behind the patterns and they tend to misuse them; often creating more comp…

I wouldn't say it's cringe. A factory is a factory. Calling it that in the code may not be the best idea, but having the shared vocabulary is nice. Basically, patterns work well when they're descriptive rather than prescriptive.

There are two cases that are unique though: state machines and visitors are so much things on their own, that you'll use those names almost every time you run into the pattern.

Re: Patterns.dev

#63

Post by dahcryn »

nl wrote: post #12

Does anyone remember the Yahoo design patterns library? It was mostly for UX pattern (eg: ways to "Rate an object") and it was really good. Almost 20 years ago.. damn. https://creativecommons.org/2006/02/14/yahoodesignpatternlib... https://web.archive.org/web/20060221111812/http://developer.... They had a great comparison of the different behaviors leaderboards could encourage in users.

we often forget how great Yahoo engineering was back in the day, sad it was destroyed by bad management and horrible business cases prioritization

Re: Patterns.dev

#64

Post by dkersten »

I hate that singleton is first.

Singletons are just globals with extra steps, and have all the same problems globals have, just people (especially juniors) think they somehow are better.

In reality they’re worse because they conflate global access with enforced single instance. You almost never need to enforce a single instance. If you only want one of something, then create only one. Don’t enforce it unless it’s critical that there’s only one. Loggers are often given as an example of a “good” singleton and yet we often need multiple loggers for things like audit logs, or separating log types.

Instead of singletons, use dependency injection, use context objects, use service locators, or… just use globals and accept that they come with downsides instead of hiding behind the false sense of code quality that is a singleton.

Re: Patterns.dev

#66

Post by esfandia »

8cvor6j844qw_d6 wrote: post #6

Looks great, time to add it to my bookmarks. Anyone has other sites like these to share? - Domain-driven design, design patterns, and antipatterns https://deviq.com/ - Refactoring and Design Patterns https://refactoring.guru/ - Standard Patterns in Choice-Based Games https://heterogenoustasks.wordpress.com/2015/01/26/standard-...

The OG site for patterns is of course the Portland Pattern Repository. I believe Ward Cunningham invented wiki for this purpose initially!

https://c2.com/ppr/

Re: Patterns.dev

#67

Post by DHRicoF »

socketcluster wrote: post #44

I find that the more senior you become, the less you rely on software design patterns. Juniors often think that learning design patterns is some kind of career hack which will allow them to skip ahead a decade of experience... There is some utility in many design patterns but the problem is that juniors often miss the nuance and the motivation behind the patterns and they tend to misuse them; often creating more comp…

For your example, if both lists are small enough, the constant factor on the cost of creating the hashmap eliminates any advantage you could have. Anyway, it's not like most places were I've seen a nested loop used for search the developer had cared. Today I am in a bad mood.

I have to touch some of the most unnerving modules in a legacy project and everything is a trap. Lot's of similar repeated code with ugly patterns and some big brain trying to hide the ugliness with layers and layers of indirections and inheritance, and calling it clean because there is a factory class. The biggest joke? each implementation have a different interface for key methods, so later you to check what instance got created.

I want to keel myself. Anyone could assist me in a seppuku?

Re: Patterns.dev

#68

Post by Izkata »

socketcluster wrote: post #44

I find that the more senior you become, the less you rely on software design patterns. Juniors often think that learning design patterns is some kind of career hack which will allow them to skip ahead a decade of experience... There is some utility in many design patterns but the problem is that juniors often miss the nuance and the motivation behind the patterns and they tend to misuse them; often creating more comp…

> For example, I've seen people write code which relies heavily on design patterns but then that same code uses an O(n^2) nested loop to find items that are common between two arrays. There is a simple 'pattern' you can use to store the items of the first array in a Set or HashMap and then finding common items is O(n) because Set and HashMap lookups are O(1)... Very useful pattern but I don't believe it has a name. I use it literally ALL the time. The idea of storing intermediate state in some kind of HashMap is a game-changer IMO but there's no name for that pattern of coding.

This is a "hash join" in relational databases. You can see it in the query planner output of at least postgres.

Re: Patterns.dev

#69

Post by dkersten »

fiddlerwoaroof wrote: post #14

I wish people would stop promoting the singleton pattern: in almost every case I’ve seen, singletons are unnecessary tech debt and solve a problem that’s better solved with some form of dependency injection (and I don’t mean the XML/YAML monstrosities various frameworks force on you but rather constructor arguments or factory functions)

Singletons are globals and should be treated the same as every other global (that is, used sparingly and with care).

Worse is that singletons enfurece a single instance which is almost always unnecessary. It’s trivial to only create as many instances as you need.

Re: Patterns.dev

#70

Post by endymion-light »

8cvor6j844qw_d6 wrote: post #6

Looks great, time to add it to my bookmarks. Anyone has other sites like these to share? - Domain-driven design, design patterns, and antipatterns https://deviq.com/ - Refactoring and Design Patterns https://refactoring.guru/ - Standard Patterns in Choice-Based Games https://heterogenoustasks.wordpress.com/2015/01/26/standard-...

+1 for refactoring.guru, find it really useful whenever i want to refactor some pre-existing code. Only wish they had a physical book!
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