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Question

Is it possible to directly return a response inside a map otherwise than doing that:

var authorized = false
roles.map { role => 
    val method = userRole.getClass.getDeclaredMethod(role.toString)
    authorized = method.invoke(userRole).asInstanceOf[Boolean]
}
authorized

or is it the only way? I've learned that it's better to avoid using var.

Thanks!

Answer 1

If you want to check if there exists an element in your list that satisfies some condition, you can use the exists method:

list.exists(value => condition(value))

Edit after the question was changed :

You can still use exists for this case, but if you want to invoke all the methods, you need to use map first (assuming your list is eager):

roles.map { role => 
    userRole.getClass.getDeclaredMethod(role.toString).invoke(userRole)
}.exists(_.asInstanceOf[Boolean])

If you don't need to call all methods (which you probably don't need to if the methods are pure), you can just use exists :

roles.exists { role =>
    userRole.getClass.getDeclaredMethod(role.toString)
            .invoke(userRole).asInstanceOf[Boolean]
}