how to implement monads in go in javascript

Monads are a way of composing functions that operate on types that have some kind of context or effect. In Go, we can implement monads using structs and methods. In JavaScript, we can use objects and functions to achieve the same result. Here's an example implementation of the Maybe monad in both Go and JavaScript:

main.go
type Maybe struct {
    Val interface{}
    Err error
}

func (m Maybe) Bind(f func(interface{}) Maybe) Maybe {
    if m.Err != nil {
        return m
    }
    return f(m.Val)
}

func (m Maybe) Map(f func(interface{}) interface{}) Maybe {
    if m.Err != nil {
        return m
    }
    return Maybe{Val: f(m.Val)}
}

func (m Maybe) OrElse(def interface{}) interface{} {
    if m.Err != nil {
        return def
    }
    return m.Val
}
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index.tsx
function Maybe(val, err) {
    this.val = val;
    this.err = err;
}

Maybe.prototype.bind = function(f) {
    if (this.err) {
        return this;
    }
    return f(this.val);
}

Maybe.prototype.map = function(f) {
    if (this.err) {
        return this;
    }
    return new Maybe(f(this.val));
}

Maybe.prototype.orElse = function(def) {
    if (this.err) {
        return def;
    }
    return this.val;
}
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In this example, the Maybe monad is used to handle computations that may result in an error. The Bind method applies a function to the value of the Maybe, returning a new Maybe with the result of the function. The Map method applies a function to the value of the Maybe and wraps the result in a new Maybe. The OrElse method returns the value of the Maybe or a default value if the Maybe contains an error.

Using monads can make code more modular and composable. By defining these methods for a particular monad, we can abstract away the details of how computations are performed and focus on the logic of our program.