How to save IF condition as Boolean Variable?

The logic on my code depends on the user who is running the macro.
e.g. if username is “abc” or “def” do something and if not do something other.
That why I use the same lengthy code of If conditions many times.
Is there any way to save IF condition as Boolean Variable ?
Appreciate for any useful comments and answers.

Option Explicit
Option Compare Text
 
Sub Run_Depends_on_Username()
     If UserName = "ABC" Or UserName = "DEF" Or UserName = "XYZ" Then
       'Code
     End If
End Sub

And this is the function to get username

Function UserName() As String
  UserName = Environ("username")
End Function

>Solution :

Generally, you can assign the result of a boolean expression directly to a variable, eg

Dim isAllowed as boolean
isAllowed = (UserName = "ABC" Or UserName = "DEF" Or UserName = "XYZ" )

' Use it:
if isAllowed Then

Alternative is to create a simple function

Function isAllowed() As Boolean
     isAllowed = (UserName = "ABC" Or UserName = "DEF" Or UserName = "XYZ")
End Function