Scope

Definition: Textual Range of Code in which an Identifier can be Referenced

Types of Scope:

Static/Lexical Scope Based on textual nesting of blocks, function definitions
Dynamic Scope Based on the sequence in which functions are called

procedure scopeDemo
   var number: Integer;

   procedure myPrint
   begin
      print number
   end

   procedure myAssign
      var number: Integer;
   begin
      number := 4;
      myPrint;
   end

begin
   number := 2;
   myAssign;
end

Visibility

Definition: Availability of a Variable in a Statement

Referencing Environment

Definition: Collection of all the names visible in a Statement