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Another problem is that a MFT sensor is smaller than full-frame format (usual in traditional 35 mm camera's), so the image will be cropped and the lenses will not be used to their full potential.
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Just started reading this (just released) book, The C# Type System (no starch press)[^] and the first chapter is kind of blowing my mind.
Step 1
Author starts out with the following example and says,
"You must use better named variables so dev users know what they mean."
Displacement(double t, double v, double s)
{
var x = v * s * Math.Cos(t);
var y = v * s * Math.Sin(t) - 0.5 * 9.81 * Math.Pow(s, 2);
return (x, y);
}Yes, that makes sense.
Step 2
Then he says,
"Oh, you can add meaning with this new idea of named arguments so users don't have to remember order that they should be passed in."
var result = Displacement(angle: .523, speed: 65, elapsedTime: 4); Ok, yes, that is good advice with the modern capabilities.
Step 3 May Blow Your Mind
He mentions that the code is still confusing because all three arguments are the same primitive type (double) and this leads into...
From the book: Primitive Obsession code smell, which describes any code that has an overreliance on primitive types—that is, those types that are built into the language, such as int, double, and string.
The solution is...
Wrap All the Primitive Types In Structs 🤯🤯🤯🤯🤯
public struct Angle
{
public double Size {get; set;}
}
public struct Speed
{
public double Amount {get; set;}
}
The Paradigm Has Shifted
Now, when the user attempts to call the Displacement method the compiler will know that the argument type is wrong.
Now, there's no way to pass the wrong value into the method, because the compiler will know the type.
Wow, that is a very different paradigm!!
Step 4 Is Immutability
Now, make each struct immutable so that it cannot be altered after construction.
public readonly struct Speed
{
public Speed(double amount)
=> Amount = amount;
public double Amount {get;}
}
I began learning OOP back in 1991 or so and it was much different then with a strong focus on Inheritance. Of course we all learned the pain of inheritance and then the Gang Of Four said,
"prefer composition over inheritance" and that changed a lot of thought on OOP.
Design to a interface and not a implementation.
It is interesting now because there seems to be a switch from Class-focus (heap-based objects) to Struct-focus (stack-based objects) at this current time.
Keep in mind that when Java was created that the designers literally made everything a Class.
I mean, basically C# is that way too with Object at the bottom.
In iOS / SwiftUI they have officially said, "If you create a new thing then create a struct not a class" and they explain why.
What Are Your Thoughts?
Anyways, what do you think about this "Primitive Obsession code smell"?
I see the value in it -- and I'm assuming that the people promoting this are saying do this for specific things in the domain and not all of them.
I cannot image wrapping all primitives in structs and having that many extra types. It feels odd but I can definitely see the value / benefit. But it's really odd after all these years.
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I agree that Primitive Obsession is a code smell. It can easily cause bugs when, for example, a plain integer is interpreted as a time duration. Was that in seconds? Milliseconds? Microseconds? There have been articles about the topic on this site. Here's one of them, but in C++:
Units and measures for C++ 11[^]
Fixing that code smell in a legacy system can be quite a bit of work.
I don't subscribe to the "prefer composition over inheritance" mantra when stated that simply. If B is a type of A, B should derive from A (inheritance). But if B only has an A, but also other behavior that has nothing to do with an A, B should contain an instance of A (composition). The problem with using composition when inheritance is called for is that B ends up cloning most of A's interface and forwarding to it.
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Greg Utas wrote: It can easily cause bugs when, for example, a plain integer is interpreted as a time duration. Was that in seconds? Milliseconds? Microseconds?
Yes, I agree. That is a very good example of where this struct wrapper would be highly beneficial.
And, I do like the discussion around "using more structs". It is just interesting that in the past, it was "everything is a class" and to see that re-thought.
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In C++, there's no difference between class and a struct, so that comparison with C# is likely to be misleading. In C++, the two keywords often have different semantics by convention, but they're the same to the compiler. If you look at the STL's <chrono>, there's no way to confuse a duration in seconds with one in milliseconds. Their object wrapper precludes it.
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raddevus wrote: Anyways, what do you think about this "Primitive Obsession code smell"?
It seems like the book author is someone trying to sound smarter than they are. Just because someone writes a book doesn't make them a genius. Now, I do agree that primitive obsession is bad, but so is struct obsession. A struct won't inherently prevent a coder from mistaking milliseconds for seconds (to borrow from this thread's example). But, what it does do is offer more complexity in an application that may otherwise not be needed.
A lot of these "new" ideas are just rehashed old ideas from JavaScript. I'm dead serious. It's just people looking for something to do rather than go outside. In JavaScript, some folks love to use an object as a parameter for everything. It's the loose and fast version of a struct in C#. It's just as ridiculous to expect an object as a single param in every last routine.
The problem is, the obsession or abuse of any one concept. Average coders take one little thing and run with it because it's the new shiny doodad. Abusing structs is no better. It's just change for change's sake while pretending to be smart. It's about balance.
raddevus wrote: Step 4 Is Immutability
To the point of the book, to make each struct read only is a good idea. But, to the point of "prefer composition over inheritance", both Java and C# were literally designed with an OOP paradigm in mind. Move to a functional language if you want to start acting functional.
In regard to immutability, you can use a sealed class in Java and C# as well.
The irony is, all this struct talk is reminding me of C. People always said C sucked because it doesn't support classes. And yet, here we are. People just following the hype train because people looking to change something for no real gain and refuse to go outside. And I say this as a dude who loves functional programming, C# wasn't designed that way.
Jeremy Falcon
modified 25-Sep-23 14:06pm.
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That was a great read. I had many of the same thoughts as I originally read the material.
Jeremy Falcon wrote: The irony is, all this struct talk is reminding me of C. People always said C sucked because it doesn't support classes. And yet, here we are. People just following the hype train
Agree 100%!!
Thanks for being so direct in your post. I wondered if there were others out there who thought the same thing. It's interesting that so many things have been done in the past and then along comes someone who says, "Hey, I got this shiny new thing." 
I do see the benefit of this used in small special cases though. But, of course, once a certain set of people read about "Primitive Obsession" they will be obsessed with wrapping all primitives in structs.  It's the latest shiny thing, after all.
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Any time man. The longer you're in the industry, the more you see these patterns emerge over and over and over.
Here's another example, in the 90s when MS started pushing XML like crazy. Average coders were all like "omg clear text file formats". But, a decade prior we had SGML that did the same exact thing. SGML also required a DTD. Sure, XML was more strict... but it was nothing new in concept. And all these kiddies came along acting like they cured cancer because binary file formats was baaaaaaaad.
Even made its way to the web. XML this. XML that. But it was nothing new. Fortunately, the web eventually said screw that... it's bloated. Now JSON is the defacto non-official standard in the web world, and we use conventions rather than a DTD.
But the point is, if you used SGML for your typical file format in the 80s... I guarantee you coders would've came along saying how stupid that is.
Jeremy Falcon
modified 25-Sep-23 14:19pm.
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The SGML v XML discussion is a perfect example of it, for sure.
And speaking of JSON -- the detractors for JSON want this new, new, new THING!!
(RUST uses it)
It's called TOML (Tom's Obvious, Minimal Language[^]).
TOML is so amazing!! It's so new. It's never been seen before!!!! Squeeeeee!!
Oh, wait, Windows 3.1 Ini files[^] used that same format. 😅😆🤣🤓
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raddevus wrote: Oh, wait, Windows 3.1 Ini files[^] used that same format.
Ha ha ha ha. That's so true. In fact, one of the reasons I haven't really decided to learn Rust yet is it's too opinionated.
Jeremy Falcon
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Jeremy Falcon wrote: one of the reasons I haven't really decided to learn Rust yet is it's too opinionated.
But it is recommended by the big players... how can you say that?
M.D.V. 
If something has a solution... Why do we have to worry about?. If it has no solution... For what reason do we have to worry about?
Help me to understand what I'm saying, and I'll explain it better to you
Rating helpful answers is nice, but saying thanks can be even nicer.
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Because I have a brain? 
Jeremy Falcon
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Jeremy Falcon wrote: Because I have a brain and I know how to use it for that rare thing called critical thinking ? 
FTFY
(Sorry, I forgot the /s at the end of my previous comment)
M.D.V. 
If something has a solution... Why do we have to worry about?. If it has no solution... For what reason do we have to worry about?
Help me to understand what I'm saying, and I'll explain it better to you
Rating helpful answers is nice, but saying thanks can be even nicer.
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But they are completely different: INI files use a ";" for comments and TOML uses a "#". 
Bond
Keep all things as simple as possible, but no simpler. -said someone, somewhere
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Jeremy Falcon wrote: in the 90s when MS started pushing XML like crazy.
It most definitely was not limited to MS! I never even expired them as very dominating in the XML rush. It was always the *nix guys who insisted on all information in the system being stored as 7-bit ASCII so any hacker would be able to modify any system data using ed for modifying it.
To pick one example: Open Office XML entered the market several years before MS changed from binary formats to OOXML.
I never loved XML (and some of the tools even less than the plain XML format, e.g. XSLT). I went to a Digital Library conference around 2002, and for the first twelve presentations I visited, eleven of them made a major issue of their use of XML and all its benefits. Methinks not. But the issue was not up for discussion; it was settled, carved in stone: "XML is good for you! Always!"
After XML we went into a period of 'Every decent programmer has his own data description language'. One project I was in - and it wasn't a very big one - used four different description languages, all of which covered the same functionality. If JSON is the one to kick out all the others, it is a step forward, no matter its weaknesses. But it seems like new alternatives keep popping up all the time. Maybe JSON is The Answer this year, but I am fully prepare for it being thrown to the wolves within a couple of years.
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Jeremy Falcon wrote: The irony is, all this struct talk is reminding me of C.
In my first University level programming class, Pascal was the programming language. We were taught a programming discipline where all attributes relating to a phenomenon (such as a physical object) where put together in a struct. All manipulation of variables of a given struct type were done by a set of functions and procedures (those are the Pascal terms) declared together with the struct type definition. All functions / procedures should take a pointer to a struct as its first argument.
The course included creating general struct types, and including these in more specialized substruct types adding more attributes. It also included handling polymorphic types, using the variant structure facility of Pascal.
I took this first course in object oriented use of Pascal structs (no, we didn't label it as such!) in the fall of 1977.
When OO arrived (C++ in 1985), we moved the first argument - the struct pointer - to make a prefix to the function / procedure name, with a separating dot. The biggest change was the OO term, and starting to say 'method' rather than function / procedure. Sub/superclasses, polymorphism and a general OO mindset had been in place for several years; we just didn't know it by that name.
So quite fancy use of structs for creating objects / blackboxed types has at least 45 years on its back. Back then, some of it relied on programming discipline, not compiler support - but use of structs to create distinct types, as the book author suggests, doesn't really have any compiler support at the concept level, either.
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Extremely fascinating story. Thanks for sharing.
As I was reading your description...
trønderen wrote: All manipulation of variables of a given struct type were done by a set of functions and procedures (those are the Pascal terms) declared together with the struct type definition. All functions / procedures should take a pointer to a struct as its first argument.
...I was thinking, that sounds like a class (or just a half-step away) -- data encapsulation with associated functions that work on the data. Very interesting.
trønderen wrote: Back then, some of it relied on programming discipline, not compiler support
I have talked about this for a long time.
1. If you don't have disciplined devs (engineering mentality of "do the right thing"), then
2. you better have a technology that forces the discipline (example, private vars cannot be manipulated outside class).
This is also why old timers (who had to have a disciplined mindset so they didn't cause themselves problems) see a lot of the new stuff as just fluff.
Two Thoughts
1. There are people who still create total crap, even with all the tools and automated discipline we have now.
2. There were people in the past who created amazing feats of software, even though all the discipline was required to be inside them.
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Quote: This is also why old timers (who had to have a disciplined mindset so they didn't cause themselves problems) see a lot of the new stuff as just fluff.
I resemble that remark.
"They have a consciousness, they have a life, they have a soul! Damn you! Let the rabbits wear glasses! Save our brothers! Can I get an amen?"
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Additionally, not only old timers, people like me or d2k that have worked / work with limited resources (PLCs, Embedded...) can be counted in too
M.D.V.
If something has a solution... Why do we have to worry about?. If it has no solution... For what reason do we have to worry about?
Help me to understand what I'm saying, and I'll explain it better to you
Rating helpful answers is nice, but saying thanks can be even nicer.
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Jeremy my man, you said it all and very well indeed.
Software Zen: delete this;
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Thanks buddy.
Jeremy Falcon
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Is "prefer composition over inheritance" functional? I'm not sure that it is. I think it's simply another OO approach to code re-use. Personally, I'm not against a certain level of inheritence, but I much prefer composing objects for functionality.
I'm not sure if I'm missing something but what has a sealed class to do with immutability. A class is immutable if you can't change it's data, a sealed class means it can't be inherited from.
I agree on the C# funtion point, it annoys me how everything needds to now be functional, I chose C# for it's OO properties, when I want to do funtional programming I'll use F#. (it'll be a pretty cold day in hell for that to happen though  )
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Chris Baker 2021 wrote: Is "prefer composition over inheritance" functional?
In functional programming that concept is talked about a lot. I mean a lot. Mainly because in purely functional programming you don't have inheritance. So, when I speak of composition, I'm specifically referring to functional composition.
Function composition (computer science) - Wikipedia
There's also object composition in OOP-land. Not really sure which one came first though...
Jeremy Falcon
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Jeremy Falcon wrote: Not really sure which one came first though
I'm reasonably sure functional composition came first. I think Lisp predates the OO paradigm by quite a bit. And if I remember correctly, in the early days, Lisp was purely functional.
Keep Calm and Carry On
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Thanks for that. That's what I thought too but wasn't sure.
Jeremy Falcon
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