Not sure if the terminology in the title is 100% correct, but what I mean is easily illustrated by this example:
class MyClass{
String str = '';
MyClass(this.str);
}
void main() {
MyClass obj1 = MyClass('obj1 initial');
print(obj1.str);
doSomething(obj1);
print(obj1.str);
doSomethingElse(obj1);
print(obj1.str);
}
void doSomething(MyClass obj){
obj.str = 'obj1 new string';
}
void doSomethingElse(MyClass obj){
obj = MyClass('obj1 new object');
}
This will print
obj1 initial
obj1 new string
obj1 new string
But what if I wanted doSomethingElse()
to actually modify what obj1
is referencing, so that the output would be:
obj1 initial
obj1 new string
obj1 new object
Is this possible in Dart, and if so, how?
No, Dart does not pass arguments by reference. (Without something like C++'s complex type system and rules, it's not clear how it would work if the caller didn't bind the argument to a variable.)
You instead could add a level of indirection (i.e., by putting obj1
inside another object, such as a List
, Map
, or your own class). Another possibility would be to make doSomethingElse
a nested function, and then it could directly access and modify variables in the enclosing scope.
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