sum_types_generator 0.1.2+4 sum_types_generator: ^0.1.2+4 copied to clipboard
sum_types and sum_types_generator packages together define a code generator enabling sum-types in Dart.
sum_types and sum_types_generator #
sum_types and sum_types_generator packages together define a code generator enabling sum-types in Dart.
Features #
Core:
- Const-constructors
- Extensible sum-types (
Nat.toInt()
) - No-payload cases (
Case<void>(name: "zero")
→Nat.zero()
) - Default case-names (
Case<String>()
→JSON.string("some")
) - Recursive sum-types (
Case<_Nat>(name: "next")
→Nat.next(Nat.zero())
) - Generic sum-types (
Either<Left, Right>
) - Exhaustive in-line
iswitch
- Inexhaustive in-line
iswitcho
(withotherwise:
case)
Trivia:
- Equality test
- Hash function
- To string conversion
Example #
In example/lib/example.dart you can find a couple of sum-type declarations and in example/lib/example.g.dart the generated code.
This one models the natural numbers (with zero):
@SumType([
Case<void>(name: "zero"),
Case<_Nat>(name: "next"),
])
mixin _Nat implements _NatBase {
Nat operator +(Nat other) => iswitch(
zero: () => other,
next: (next) => Nat.next(next + other),
);
int toInt() => iswitch(
zero: () => 0,
next: (next) => 1 + next.toInt(),
);
}
Development #
Find the upcoming development plans in the project planner.