There's Austral https://austral-lang.org/ for linear types, I'm not sure what is the state of the language but it has a nice tutorial about linear types.
jnpnj · 1h ago
Newb question, aren't phantom types and typestates a subset (or cousin) of linear types ?
burakemir · 57m ago
No. A phantom type is a type whose only use is to communicate a constraint on a type variable, without having a runtime value that corresponds to it.
Typestate is a bit closer: it communicates some property where an operation (typically a method invocation) changes the property and hence the typestate. But there isn't necessarily a mechanism that renders the value in the old typestate inaccessible. When there is, then this indeed requires some linearity/affinity ("consuming the object"), but typestate is something built "on top".
scythmic_waves · 1h ago
Sorry off topic but I love the styling of this site.
Typestate is a bit closer: it communicates some property where an operation (typically a method invocation) changes the property and hence the typestate. But there isn't necessarily a mechanism that renders the value in the old typestate inaccessible. When there is, then this indeed requires some linearity/affinity ("consuming the object"), but typestate is something built "on top".