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0 pointsenriquto6y ago0 comments

> No, encoding additional information in unused bits of an int that you return is stupid over-engineering that needs multiple textbooks to grok. Option<char>, on the other hand, is the simplest possible solution for this problem.

What kind of wicked education you had for this to be the case?

My dad taught me about bits and bytes and words when I was a kid, and by 16 I had a quite solid grasp of it (without any textbook). Then I studied several years and got a phd in applied math (mostly numerical pde, and that involved a lot of programming). Then I have spent 15 more years doing math and programming in several languages (mostly C and Python) and getting paid for teaching data science and signal processing to people who got on to have fruitful jobs in industry. Today, I read the wikipedia page about "option type" [1] and the one about about type theory [2], which seems a prerequisite, and couldn't understand a word.

[1] https://en.wikipedia.org/wiki/Option_type

[2] https://en.wikipedia.org/wiki/Type_theory

0 comments

wk_end6y ago

Surely if you have a PhD in applied math you've seen that Wikipedia will often foreground dense theoretical issues, even for topics with straightforward practical applications.

You do not need to understand theoretical type theory to understand options. It's just like a pointer that can be NULL except the compiler makes sure you can't accidentally dereference it if it is. Algebraic data types in general are basically just structs and tagged unions, except the compiler makes sure you can't screw the tags up.

Like, dude, by your own account, you're pretty smart; that's the point of your last paragraph, right? There are, at this point, hoards of Rust and Scala and Swift and Kotlin programmers who can figure out how option types work, and don't seem to have too much of a problem with it and pretty much universally think they're great. Are they actually just smarter than you?

enriqutoOP6y ago

> Are they actually just smarter than you?

Sure they are. Or at least they do not hold an irrational, primary hatred of over-abstraction like I do. In math there's also people like this, who work in stuff like category theory, logic and whatnot. Fortunately, they are a mostly controlled minority.

empath756y ago

I’m a community college drop out and have never taken a CS class and I use options in my code all the time.

It’s just a wrapper around some value that is either Some(value) or None and you need to unwrap it and handle both possibilities for your code to compile.

You don’t need to know anything about monads or ADT’s to understand it.

enriqutoOP6y ago

But do you understand that some values of a 32 bit int can be used to encode meta-data about a 8 bit char?

If you understand both, which one is conceptually easier to you?

dmit6y ago

Option<T> is conceptually easier because:

1) It applies exactly the same way to any type, not just char.

2) You don't need to read the man page for every single function that returns an int on the off chance that said int actually contains a bool, a char, or a short plus additional flags.

epolanski6y ago

option obviously.

I just do not understand what the problem with Option is.

It's either Some(1) or None. If it's some you have the value, otherwise you handle the fact you don't have it.

It's so simple and basically every modern language uses it to handle nullable types.

empath756y ago

Options for sure, at least in rust.

Rust has tons of help dealing with options built into the language.

j / k navigate · click thread line to collapse

0 pointsenriquto6y ago0 comments

What kind of wicked education you had for this to be the case?

[1] https://en.wikipedia.org/wiki/Option_type

[2] https://en.wikipedia.org/wiki/Type_theory

0 comments

wk_end6y ago

Surely if you have a PhD in applied math you've seen that Wikipedia will often foreground dense theoretical issues, even for topics with straightforward practical applications.

enriqutoOP6y ago

> Are they actually just smarter than you?

empath756y ago

I’m a community college drop out and have never taken a CS class and I use options in my code all the time.

It’s just a wrapper around some value that is either Some(value) or None and you need to unwrap it and handle both possibilities for your code to compile.

You don’t need to know anything about monads or ADT’s to understand it.

enriqutoOP6y ago

But do you understand that some values of a 32 bit int can be used to encode meta-data about a 8 bit char?

If you understand both, which one is conceptually easier to you?

dmit6y ago

Option<T> is conceptually easier because:

1) It applies exactly the same way to any type, not just char.

2) You don't need to read the man page for every single function that returns an int on the off chance that said int actually contains a bool, a char, or a short plus additional flags.

epolanski6y ago

option obviously.

I just do not understand what the problem with Option is.

It's either Some(1) or None. If it's some you have the value, otherwise you handle the fact you don't have it.

It's so simple and basically every modern language uses it to handle nullable types.

empath756y ago

Options for sure, at least in rust.

Rust has tons of help dealing with options built into the language.

j / k navigate · click thread line to collapse