Developers have a bad habit of adding mutable fields to plain old data objects in Go though, so even if it's immutable now, it's now easy for a developer to create a race down the line. There's no way to indicate that something must be immutability at compile-time, so the compiler won't help you there.
Good points. I have also heard others say the same in the past regarding Go. I know very little about Go or its language development, however.
I wonder if Go could easily add some features regarding that. There are different ways to go about it. 'final' in Java is different from 'const' in C++, for example, and Rust has borrow checking and 'const'. I think the language developers of the OCaml language has experimented with something inspired by Rust regarding concurrency.
Rust's `const` is an actual constant, like 4 + 1 is a constant, it's 5, it's never anything else, we don't need to store it anywhere - it's just 5. In C++ `const` is a type qualifier and that keyword stands for constant but really means immutable not constant.
This results in things like you can "cast away" C++ const and modify that variable anyway, whereas obviously we can't try to modify a constant because that's not what the word constant means.
In both languages 5 += 3 is nonsense, it can't mean anything to modify 5. But in Rust we can write `const FIVE: i32 = 5;` and now FIVE is also a constant and FIVE += 3 is also nonsense and won't compile. In contrast in C++ altering an immutable "const" variable you've named FIVE is merely forbidden, once we actually do this anyway it compiles and on many platforms now FIVE is eight...
Yeah, indeed.
Developers have a bad habit of adding mutable fields to plain old data objects in Go though, so even if it's immutable now, it's now easy for a developer to create a race down the line. There's no way to indicate that something must be immutability at compile-time, so the compiler won't help you there.
Good points. I have also heard others say the same in the past regarding Go. I know very little about Go or its language development, however.
I wonder if Go could easily add some features regarding that. There are different ways to go about it. 'final' in Java is different from 'const' in C++, for example, and Rust has borrow checking and 'const'. I think the language developers of the OCaml language has experimented with something inspired by Rust regarding concurrency.
Rust's `const` is an actual constant, like 4 + 1 is a constant, it's 5, it's never anything else, we don't need to store it anywhere - it's just 5. In C++ `const` is a type qualifier and that keyword stands for constant but really means immutable not constant.
This results in things like you can "cast away" C++ const and modify that variable anyway, whereas obviously we can't try to modify a constant because that's not what the word constant means.
In both languages 5 += 3 is nonsense, it can't mean anything to modify 5. But in Rust we can write `const FIVE: i32 = 5;` and now FIVE is also a constant and FIVE += 3 is also nonsense and won't compile. In contrast in C++ altering an immutable "const" variable you've named FIVE is merely forbidden, once we actually do this anyway it compiles and on many platforms now FIVE is eight...
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