Alternative for break operation in scala

Question

I want to create something like below in scala.

I am writing it in c, but i want to do exactly same in scala.

int bool = 0,i,j;
for(j=0;j<5;j++){
    for(i=0;i<5;i++){
        if(i==3)
           bool=1;
           break;
    }
    if(bool==0)
        continue;
    some function....
}

What's the purpose of that `continue` statement? It's the end of the outer for-loop anyway, so it's always going to continue. — Zoltán, Nov 02 '15 at 12:10
No actually after continue statement there is some function I am calling — Mahek Shah, Nov 02 '15 at 12:11
Its just example. In my code there is other variable which keeps on changing in every loop and `i` is compared with that function. — Mahek Shah, Nov 02 '15 at 12:15
Just throw exceptions and handle them. That is the supposed scala way for breaking loops — ayvango, Nov 02 '15 at 12:16
You need to express all of this in your code sample. It changes what you're asking for significantly. — Zoltán, Nov 02 '15 at 12:16
@Zoltán give me some time.. I will edit this post and come up with actual problem.. Thanks for reply :) — Mahek Shah, Nov 02 '15 at 12:22
I got the answer.. I can use exist method which will give the same output as I want — Mahek Shah, Nov 03 '15 at 04:52

Andreas Neumann · Answer 1 · 2015-11-02T12:23:03.497

3

In Scala the preferred way is to use methods of the Standard Library and no clearly supported, good way to break out of functions.

An option to achieve the result wished is to use takeWhile . If some side effecting logic is wished that can be applied by using foreach. An additional check can for example be introduce by introducing a predicate.

The given example code could be improved by using the predicate in a filter, but I think one gets the basic idea.

Define the functions

def someFunction(x: Int): Unit = if ( predicate(x)) println(x)
def predicate : (Int) => Boolean = _ % 2 == 0

(0 to 5).takeWhile(_ != 3) foreach someFunction

Example

(0 to 5).takeWhile(_ != 3) foreach someFunction
0
2
someFunction: (x: Int)Unit
predicate: Int => Boolean

edited Nov 02 '15 at 12:23

answered Nov 02 '15 at 12:12

Andreas Neumann

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Thanks for reply.. I actually want to use that bool variable as a decision making variable in next. So using above code how can I achieve that goal? – Mahek Shah Nov 02 '15 at 12:14
@ Andreas thanks for help. Its not actually I want but your answer help me to reach there – Mahek Shah Nov 02 '15 at 12:19
Added the code needed to use the the bool as decission. – Andreas Neumann Nov 02 '15 at 12:19

Alternative for break operation in scala

1 Answers1

Define the functions

Example