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Diffstat (limited to 'TYPES.md')
| -rw-r--r-- | TYPES.md | 30 |
1 files changed, 28 insertions, 2 deletions
@@ -111,6 +111,34 @@ Generics are replaced with concrete types at compile time (monomorphization) bas Constrained generics have two syntaxes: the constraint can be directly on a parameter, leaving off the `[T]` box, or it may be defined within the box as `[T: int | float]` for easy reuse in the parameters. +## Reference types + +Types are typically constructed as value on the stack. That is, without any level of indirection: and so type declarations that recursively refer to one another would not be allowed. However, Puck provides two avenues for indirection. + +Reference types can be one-of: +- `ref T`: An automatically-managed reference to type `T`. +- `ptr T`: A manually-managed pointer to type `T`. (very) unsafe. + +In addition, `var T` may somewhat be considered a reference type as it may implicitly create a `ref` for mutability if the type is not already `ref`: but it is only applicable on parameters. + +``` +type Node = ref struct + left: Node + right: Node + +type AnotherNode = struct + left: ref AnotherNode + right: ref AnotherNode + +type BinaryTree = ref struct + left: BinaryTree + right: BinaryTree +``` + +The compiler abstracts over `ref` types to provide optimization for reference counts: and so neither a distinction between `Rc`/`Arc`/`Box`, nor a `*` dereference operator is needed. +Much care has been given to make references efficient and safe, and so `ptr` should be avoided if at all possible. The compiler will yell at you if you use it (or any other unsafe features). +These types are delved into in further detail in the section on memory management. + ## Advanced Types The `type` keyword is used to declare custom types. @@ -119,7 +147,5 @@ Custom types can be one-of: - `tuple`: An ordered collection of types. Optionally named. - `struct`: An unordered, named collection of types. May have default values. - `enum`: Powerful algebraic data types a la Rust. - - undecided: ordinal by default, which sacrifice their ordinality when assigned static values? probably a bad idea. could be ordinal by ordering in declaration. i think rust is ordinal by alphabetical order, which is weird?? i wonder why - `concept`: typeclasses. they have some unique syntax - `distinct`: a type that must be explicitly converted - - useful for preventing sql injections, ascii/unicode fuckups, etc |