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Scope

• How is an invocation associated with the definition it invokes?
  • begin
       var A: newint;
       proc P = begin var C: newint
          in C:=@A end
       proc Q = begin var B: newint; A: newint
          in A:=1; call P end
    in A:=0; call P; call Q; end
  • Does C become 0 or 1?
• Static Scoping
  • Invocation of I is associated with definition of I whose scope contains definition.
  • Assocation between invocations and definitions can be calculated at compile-time!
  • Typing rules based on static scoping.