Call by name

• The formal is reevaluated at each use

  • Uses a thunk to implement it

• swap(i, a[i])

  • i = 1
  • a[1] = 3
  • a[3] = 17

• Doesn’t swap, and you can’t fix it

proc swap(a, b : int);

var temp : int;

begin

temp := a;

a := b;

b := temp

end;

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