Flow control statements

(B) Loops and iteration

For

JS

for(let i=0;i<10;i++){
    console.log(i);
}

Go

for i := 0; i < 10; i++ {
    fmt.Println(i)
}

While

In Go, the for's init and post statement are optional, effectively making it also a "while" statement:

JS

var i=0;
while(i<10){
    console.log(i);
    i++;
}

Go

i := 0
for i < 10 {
    fmt.Println(i)
    i++
}

Iterating over an Array/Slice

JS

['Rick','Morty','Beth','Summer','Jerry'].forEach(function(value,index){
    console.log(value + ' at index ' + index);
});

Go

for i, v := range []string{"Rick", "Morty", "Beth", "Summer", "Jerry"} {
    fmt.Printf("%v at index %d", v, i)
}

(B) If/Else

Go's if can contain an init statement, with variables declared scoped only to the if and else blocks.

Go

if value := getSomeValue(); value < limit {
    return value
} else {
    return value / 2
}

(D) Switch

The switch statement was one of the motivation for writing this document.

Go defaults to break, and fallthrough needed for otherwise.

Javascript defaults to fallthrough, and break needed for otherwise.

JS

switch (favorite) {
    case "yellow":
        console.log("yellow");
        break;
    case "red":
        console.log("red");
    case "purple":
        console.log("(and) purple");
    default:
        console.log("white");
}

Go

switch favorite {
case "yellow":
    fmt.Println("yellow")
case "red":
    fmt.Println("red")
    fallthrough
case "purple":
    fmt.Println("(and) purple")
default:
    fmt.Println("white")
}