"Immutable" in this sense simply means that the objects are constant. One could still meaningfully distinguish between equality (==) and identity (===). My guess is that there's no urgent need for this in Julia -- as a work-around, you can use a mutable type, and then not modify objects once created.
-erik On Thu, Jan 21, 2016 at 8:23 AM, Yichao Yu <[email protected]> wrote: > On Wed, Jan 20, 2016 at 7:22 PM, <[email protected]> wrote: >> Julia's immutable types are value types and mutable types are reference >> types. In the Julia docs on types there is a paragraph that begins: >> >> "It is instructive, particularly for readers whose background is C/C++, to >> consider why these two properties go hand in hand. [...]" >> >> However this paragraph only explains why value types should be immutable, it >> doesn't describe why you can't define a reference type that is immutable. >> So, why not? > > Because there's no value type at all. A immutable reference type is > effectively a value type. -- Erik Schnetter <[email protected]> http://www.perimeterinstitute.ca/personal/eschnetter/
