type_ init_ formals
Don't type annotate initializing formals.
Details
#From Effective Dart:
DON'T type annotate initializing formals.
If a constructor parameter is using
this.x
to initialize a field, then the
type of the parameter is understood to be the same type as the field. If a
a constructor parameter is using
super.x
to forward to a super constructor,
then the type of the parameter is understood to be the same as the super
constructor parameter.
Type annotating an initializing formal with a different type than that of the field is OK.
BAD:
class Point {
int x, y;
Point(int this.x, int this.y);
}
GOOD:
class Point {
int x, y;
Point(this.x, this.y);
}
BAD:
class A {
int a;
A(this.a);
}
class B extends A {
B(int super.a);
}
GOOD:
class A {
int a;
A(this.a);
}
class B extends A {
B(super.a);
}
Enable
#
To enable the
type_init_formals
rule, add
type_init_formals
under
linter > rules
in your
analysis_options.yaml
file:
linter:
rules:
- type_init_formals
If you're instead using the YAML map syntax to configure linter rules,
add
type_init_formals: true
under
linter > rules:
linter:
rules:
type_init_formals: true
Unless stated otherwise, the documentation on this site reflects Dart 3.9.2. Report an issue.