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functiondartreturn-valuereturn-type

Non-void function returns nothing dart

I have a function that returns int value but in some circumstances I want to terminate the function and return nothing.

Just to show an example:

int numberFunc(int num){
    if(num > 10){
       return; 
/* terminates the function for numbers more than 10 */
     }
    return num;
}

This works fine but I get a warning that says the function has a return type of int but it doesn’t finish with a return statement.

Will there be a problem if I use something like this and what can be a solution for that?

Thanks

Solution:

As julemand101 explained, We can return a null value. Also the code above returns a null value for numbers more than 10 so we have to take care of the possible null values later on.

Solution

  • What you properly want is to return null to indicate that the method are not returning any value:

    int numberFunc(int num){
    if(num > 10){
       return null; 
/* terminates the function for numbers more than 10 */
     }
    return num;
}

    But remember that the method which are using the result from numberFunc needs to be aware that the returned value can be null.