Constantly Confusing ‘const’

Re:Constantly Confusing ‘const’ by Nullabillity on Tuesday September 08, 2015 @06:14PM (#10188502)

> To your point however, `const` does not imply constant in the sense of other languages (like `.freeze()` does) so it does mean your target future audience is someone who is familiar with some of the nuances of recent JavaScript, an assumption that can be dangerous to make.

Does any other language than Rust implement it this way? I know Rust needs to, for the borrowing semantics.

Java does it the same way as JS. Scala and Haskell both make everything immutable by default as convention, but there's nothing preventing you from mutating a `var` field of a `val` reference, or abusing `unsafePerformIO` to modify an `IORef` from a supposedly pure context.

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Re:Constantly Confusing ‘const’ by jharger on Tuesday September 08, 2015 @06:39PM (#10188598)

C++

Assume you have a class Foo, and this:

const Foo fooInst(1, 2, 3);

if you try to call a method foo.bar() you can't, unless that method bar() is also marked const with this type of signature:

int bar() const;

Meaning that bar returns an int, but can't assign to any fields or call any other non-const methods.

Although, it does have this hideous const_cast<> operator that anyone can use to break these rules.

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