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If I want to learn F# is there a good IRC/slack channel I can get on? I'd like recommendations for libraries. I have a project I could throw at it for fun/ lear

If I want to learn F# is there a good IRC/slack channel I can get on? I'd like recommendations for libraries. I have a project I could throw at it for fun/ learning. P.S. Can someone explain this? // complex types in a few type Employee = | Worker of Person | Manager of Employee list

deleted 8y ago
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scriptdevil 8y ago
Employee, Person and list are types Worker and Manager are constructors Employee is a Sum Type i.e. it can either take a value of (Worker personObject) or (Manager [empObj1, empObj2...]) for instance, an binary tree would be type Tree a = | Leaf of a | Node of (Tree a * Tree a) Now, a Tree Int would be t = Node (Node (Leaf 1, Leaf 2), Leaf 3)
platz 8y ago
abstract class Employee {} class Worker : Employee { public Worker(Person o) {...} } class Manager : Employee { public Manager(Employee[] o) {...} }
- sparkie 8y ago
  abstract sealed class Employee { enum TAG { Worker, Manager } readonly TAG tag; Employee(TAG t) { tag = t; } public class Worker : Employee { public Worker(Person p) : base(TAG.Worker) { ... } } public class Manager : Employee { public Manager(Employee[] o) : base(TAG.Manager) { ... } } } This is a bit closer to how it is really implemented. The constructors are internal to the outer type because it is sealed, making it a closed type. Interestingly C# rejects abstract & sealed on the same type, although this is accepted on the CLR. Discriminated unions are sometimes called tagged unions because of the way they're implemented. It's typically more efficient to check the tag on the object than it is to test its type. The tag is used when pattern matching over the object.
  - platz 8y ago
    Ok, the idea was to communicate to someone who has never seen an ADT before what kind of thing it is, rather than a full decompilation of how it's really implemented, but thanks for that too.
phillipcarter 8y ago
Yes! If you join the F# Software Foundation[0] (100% free, no obligation to donate anything, etc.) you get access to a rather active slack. [0]: http://foundation.fsharp.org/membership http://foundation.fsharp.org/membership

deleted 8y ago

[deleted]

scriptdevil 8y ago

Employee, Person and list are types Worker and Manager are constructors Employee is a Sum Type i.e. it can either take a value of (Worker personObject) or (Manager [empObj1, empObj2...]) for instance, an binary tree would be type Tree a = | Leaf of a | Node of (Tree a * Tree a) Now, a Tree Int would be t = Node (Node (Leaf 1, Leaf 2), Leaf 3)

platz 8y ago

abstract class Employee {} class Worker : Employee { public Worker(Person o) {...} } class Manager : Employee { public Manager(Employee[] o) {...} }

sparkie 8y ago
abstract sealed class Employee { enum TAG { Worker, Manager } readonly TAG tag; Employee(TAG t) { tag = t; } public class Worker : Employee { public Worker(Person p) : base(TAG.Worker) { ... } } public class Manager : Employee { public Manager(Employee[] o) : base(TAG.Manager) { ... } } } This is a bit closer to how it is really implemented. The constructors are internal to the outer type because it is sealed, making it a closed type. Interestingly C# rejects abstract & sealed on the same type, although this is accepted on the CLR. Discriminated unions are sometimes called tagged unions because of the way they're implemented. It's typically more efficient to check the tag on the object than it is to test its type. The tag is used when pattern matching over the object.
- platz 8y ago
  Ok, the idea was to communicate to someone who has never seen an ADT before what kind of thing it is, rather than a full decompilation of how it's really implemented, but thanks for that too.

phillipcarter 8y ago

Yes! If you join the F# Software Foundation[0] (100% free, no obligation to donate anything, etc.) you get access to a rather active slack. [0]: http://foundation.fsharp.org/membership http://foundation.fsharp.org/membership