Code Inspection: Field can be made readonly (non-private accessibility)
Say you have decided to make a Person
class, initialized only via the constructor, but with publicly available fields. You go ahead and implement the following:
public class Person
{
public string Name;
public int Age;
public Person(string name, int age)
{
Name = name;
Age = age;
}
public override string ToString() =>
$"Name: {Name}, Age: {Age}";
}
Public Class Person
Public Name As String
Public Age As Integer
Public Sub New(name As String, age As Integer)
Me.Name = name
Me.Age = age
End Sub
Public Overrides Function ToString() As String
Return String.Format("Name: {0}, Age: {1}", Name, Age)
End Function
End Class
If the solution-wide inspection is enabled, JetBrains Rider will detect that Name
and Age
fields are only being assigned in the constructor and offers to create an additional safeguard — by marking them readonly
, we get to ensure that neither this class nor its users will inadvertently assign new values to these fields.
For the solution-wide inspection to work, you need either or both of the following:
The simplified global usage checking is enabled — Show unused non-private type members when solution-wide analysis is off on the page of JetBrains Rider settings (Ctrl+Alt+S).
The solution-wide analysis is enabled — Enable solution-wide analysis on the page of JetBrains Rider settings (Ctrl+Alt+S).
Note that even if a symbol has no direct usages in your solution and JetBrains Rider warns you about it, there could be cases where symbols are used indirectly — e.g. via reflection — or they could just be designed as public API. In all those cases you would want to suppress the usage-checking inspection for the symbol in question, and there are several ways to do so:
The recommended way is to decorate the implicitly used symbols with code annotation attributes. There are two attributes for this purpose: [UsedImplicitly] and [PublicAPI], which are functionally similar, but let you and your teammates understand how the symbol is actually used.
You can also suppress usage-checking inspections with any custom attribute. To do so, mark the definition of that attribute with the [MeansImplicitUse] attribute.
And finally, you can suppress a specific usage-checking inspection as any other code inspection with a suppression comment or a suppression attribute.