Skip Navigation
Need to register a domain for business and get a simple website up and running in the USA - tips?
  • If you create accounts on various sites with an email address on your new domain keep a list of those. If decide to let the domain expire you need to close the accounts beforehand, otherwise someone else can get access if they purchase the domain.

    Also you will likely be playing for the domain forever, so just register/renew it for 10 years, maybe you'll also get a discount.

  • What is an easy instrument to learn?
  • The recorder. It's easy to get started, there is a lot of good information online (look up Sarah Jeffery), and professional plastic instruments are very cheap. It also requires no special care and doesn't need maintenance, since it has no moving parts.

    The downside is that in order to play larger recorders your hands need to stretch a bit, so I'm no sure if that is a problem if you have joint issues.

    The other option is a hand ocarina, but it is very hard to even make a sound, even harder to make it clear and consistent. Also you need to play entirety by ear. It's a fun challenge, though.

  • Why I Left NixOS for Ubuntu
  • A package is reproducible if you use the same inputs, run the build, and get the same outputs.

    The issue is that the build can produce different outputs given the same inputs. So you need to modify the build or patch the outputs. This is something that is being worked on by most distributions: https://reproducible-builds.org/who/projects/

    NixOS is not special in that regard nor are all NixOS packages reproducible.

  • If Inheritance is so bad, why does everyone use it?
  • As you already figured out the types are sets with a certain number of elements.

    Two types are isomorphic if you can write a function that converts all elements of the first one into the elements of the second one and a function which does the reverse. You can then use this as the equality.

    The types with the same number of elements are isomorphic, i.e True | False = Left | Right. For example, you can write a function that converts True to Left, False to Right, and a function that does the reverse.

    Therefore you essentially only need types 0, 1, 2, 3, ..., where type 0 has 0 elements, type 1 has 1 element, etc. and all others are isomorphic to one of these.

    Let's use (*) for the product and (+) for the sum, and letters for generic types. Then you can essentially manipulate types as natural numbers (the same laws hold, associativity, commutativity, identity elements, distributivity).

    For example:

    2 = 1 + 1 can be interpreted as Bool = True | False

    2 * 1 = 2 can be interpreted as (Bool, Unit) = Bool

    2 * x = x + x can be interpreted as (Bool, x) = This of x | That of x

    o(x) = x + 1 can be interpreted as Option x = Some of x | None

    l(x) = o(x * l(x)) = x * l(x) + 1 can be interpreted as List x = Option (x, List x)

    l(x) = x * l(x) + 1 = x * (x * l(x) + 1) + 1 = x * x * l(x) + x + 1 = x * x * (l(x) + 1) + x + 1 = x * x * l(x) + x * x + x + 1 so a list is either empty, has 1 element or 2 elements, ... (if you keep substituting)

    For the expression problem, read this paper: doi:10.1007/BFb0019443

  • If Inheritance is so bad, why does everyone use it?
  • The sum and product types follow pretty much the same algebraic laws as natural numbers if you take isomorphism as equality.

    Also class inheritance allows adding behaviour to existing classes, so it's essentially a solution to the expression problem.

  • How to convert imperative side-effectful program to functional (in Ocaml)?
  • The way you can think of it is that in OCaml everything is implicitly wrapped in an IO monad. In Haskell the IO monad is explicit, so if a function returns something in IO you know it can perform input and output, in OCaml there is no way to tell just from the types. That means that in Haskell the code naturally stratifies into a part that does input and output and a pure core. In OCaml you can do the same thing, however it needs to be a conscious design decision.

  • InitialsDiceBearhttps://github.com/dicebear/dicebearhttps://creativecommons.org/publicdomain/zero/1.0/„Initials” (https://github.com/dicebear/dicebear) by „DiceBear”, licensed under „CC0 1.0” (https://creativecommons.org/publicdomain/zero/1.0/)OE
    oessessnex @programming.dev
    Posts 0
    Comments 35