Here’s a secret I wish someone told me in high school: literally everything is pass by value, it’s just that sometimes the value is an address. It demystified pointers for me.
They taught you about pointers in high school? The only course available to me that even touched on programming just covered how to use C to do conditionals, read keyboard input, and print text to a terminal. The bulk of the course was learning MS Office.
I mean, Rust has the additional thing that a reference is a pointer + a borrow, so it’s not quite as similar to a pass-by-value.
And as for the dereference operator, occasionally you can use it to turn a reference into an owned value, often by making a copy of the value (but in that case, you can usually also use .to_owned()).
Here’s a secret I wish someone told me in high school: literally everything is pass by value, it’s just that sometimes the value is an address. It demystified pointers for me.
That’s true in Java, not necessarily in other languages
It’s the opposite, everything is passed by reference but primitives are also addresses and therefore passed by value
You can’t pass objects or functions as value
Yeah, when I grokked that simple fact pointers became easy.
They taught you about pointers in high school? The only course available to me that even touched on programming just covered how to use C to do conditionals, read keyboard input, and print text to a terminal. The bulk of the course was learning MS Office.
That got me confused with rust references and why the dereference operator even exists as well.
I mean, Rust has the additional thing that a reference is a pointer + a borrow, so it’s not quite as similar to a pass-by-value.
And as for the dereference operator, occasionally you can use it to turn a reference into an owned value, often by making a copy of the value (but in that case, you can usually also use
.to_owned()).A case where I don’t think there’s an alternative to the dereference operator, is if you’ve got a mutable reference and you want to replace the value that’s underneath: https://play.rust-lang.org/?version=stable&mode=debug&edition=2021&gist=04621490e1d0fd6fe1af7f2e843547fb
At the very least, if you remove the asterisk, the compiler will tell you very precisely that you need to add it back.
yeah. references aren’t the same as pointers in c++ but similar, so it’s something along those lines.