Break the Loop of an Array Looping Function (Map, Foreach, etc.)

const a = ["a", "b", "c"];
for (const element of a) { // You can use `let` instead of `const` if you like
    console.log(element);
}
// a
// b
// c

how to stop Javascript forEach?

You can't break from a forEach. I can think of three ways to fake it, though.

1. The Ugly Way: pass a second argument to forEach to use as context, and store a boolean in there, then use an if. This looks awful.

2. The Controversial Way: surround the whole thing in a try-catch block and throw an exception when you want to break. This looks pretty bad and may affect performance, but can be encapsulated.

3. The Fun Way: use every().

['a', 'b', 'c'].every(function(element, index) {
  // Do your thing, then:
  if (you_want_to_break) return false
  else return true
})

You can use some() instead, if you'd rather return true to break.

How to break out from foreach loop in javascript

Use a for loop instead of .forEach()

var myObj = [{"a": "1","b": null},{"a": "2","b": 5}]
var result = false

for(var call of myObj) {
    console.log(call)
    
    var a = call['a'], b = call['b']
     
    if(a == null || b == null) {
        result = false
        break
    }
}

Using break and continue in each() and forEach()

Using Array.prototype.some and Array.prototype.every to continue/break out of functional for loops is a good thing to do

[1,2,3,null,5].every(function(v){
    if(!v) return false;  // this will break out of the loop
    // do your regular loopage lulz
});

Cannot break for-loop: Unsyntactic break

Like you yourself suggested, you are still in the map part. That is actually an arrow function expression and you are no longer in in the loop. Think of it as some function you defined elsewhere, but it's a quicker way of calling that function.

You are not using the map function as it is meant to be used in javascript. It isn't meant to be a convenient way to iterate over an array, but rather create a new array from some other array. You should change your usage of map to some form of a loop

`break` and `continue` in `forEach` in Kotlin

Edit:

According to Kotlin's documentation, it is possible to simulate continue using annotations.

fun foo() {
    listOf(1, 2, 3, 4, 5).forEach lit@ {
        if (it == 3) return@lit // local return to the caller of the lambda, i.e. the forEach loop
        print(it)
    }
    print(" done with explicit label")
}

If you want to simulate a break, just add a run block

fun foo() {
    run lit@ {
        listOf(1, 2, 3, 4, 5).forEach {
            if (it == 3) return@lit // local return to the caller of the lambda, i.e. the forEach loop
            print(it)
        }
        print(" done with explicit label")
    }
}

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Original Answer:

Since you supply a (Int) -> Unit, you can't break from it, since the compiler do not know that it is used in a loop.

You have few options:

Use a regular for loop:

for (index in 0 until times) {
    // your code here
}

If the loop is the last code in the method

you can use return to get out of the method (or return value if it is not unit method).

Use a method

Create a custom repeat method method that returns Boolean for continuing.

public inline fun repeatUntil(times: Int, body: (Int) -> Boolean) {
    for (index in 0 until times) {
        if (!body(index)) break
    }
}

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