I saw exmaple code something like:
class ModelBinding extends StatefulWidget {
ModelBinding({
Key key,
this.initialModel = const GalleryOptions(),
this.child,
}) : assert(initialModel != null),
super(key: key);
...
so I wrote something:
class Person {
String firstName;
Person({name}){
print(name);
}
}
class Employee extends Person {
Employee(String name) : assert(false), super(name: name);
}
main() {
var emp = new Employee('Jason');
}
No matter if it is assert(false)
or assert(true)
, the result is same.
So what is the meaning of assert
?
assert
is used for debugging and it simply means the condition should be true
to proceed. Let me explain:
class MyClass {
final int age;
MyClass({this.age});
void someMethod() {
// using `age` here
}
}
You might face issues in someMethod
if age
passed is null
, so to make sure it isn't null
, you use assert
like:
class MyClass {
final int age;
MyClass({this.age}) : assert(age != null, "Make sure age isn't null");
void someMethod() {
// using `age` here
}
}
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