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Technique 1: Static Chains

• A static chain is a chain of static links that connects certain ARIs

• The static link in an ARI for subprogram A points to one of the ARIs of A's static parent

• The static chain from an ARI connects it to all of its static ancestors

• To find the declaration for a reference to a nonlocal variable:
  • The compiler can easily determine how many levels of scope separate the current subprogram from the definition
  • Just walk the static chain the correct number of steps

• Static_depth is an integer associated with a static scope whose value is the depth of nesting of that scope