Spyke

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Golang be like

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Nope. Monads enable you to redefine how statements work.

Let's say you have a program and use an Error[T] data type which can either be Ok {Value: T} or Error:

var a = new Ok {Value = 1};
var b = foo();
return new Ok {Value = (a + b)};

Each statement has the following form:

var a = expr;
rest

You first evaluate the "expr" part and bind/store the result in variable a, and evaluate the "rest" of the program.

You could represent the same thing using an anonymous function you evaluate right away:

(a => rest)(expr);

In a normal statement you just pass the result of "expr" to the function directly. The monad allows you to redefine that part.

You instead write:

bind((a => rest), expr);

Here "bind" redefines how the result of expr is passed to the anonymous function.

If you implement bind as:

B bind(Func[A, B] f, A result_expr) {
   return f(result_expr);
}

Then you get normal statements.

If you implement bind as:

Error[B] bind(Func[A, Error[B]] f, Error[A] result_expr) {
   switch (result_expr) {
       case Ok { Value: var a}:
           return f(a);
       case Error:
           return Error;
   }
}

You get statements with error handling.

So in an above example if the result of foo() is Error, the result of the statement is Error and the rest of the program is not evaluated. Otherwise, if the result of foo() is Ok {Value = 3}, you pass 3 to the rest of the program and you get a final result Ok {Value = 4}.

So the whole idea is that you hide the if Error part by redefining how the statements are interpreted.

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Are emacs and neovim worth it?

Editing in (neo)vim is akin to live programming in a very terse programming language. You can also create your own commands (keybindings) and repeat snippets multiple times (macros). This is amazingly powerful if you need to convert between two formats or extract some information.

The UI is not a highlight of this editor.

It also takes years before selecting the commands becomes mostly subconscious. It is definitely a long term investment.

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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.