This is documentation for Mathematica 6, which was
based on an earlier version of the Wolfram Language.
View current documentation (Version 11.2)


is an option for Dialog which can give an expression to evaluate before the dialog starts.
  • You must use a delayed rule of the form DialogProlog:>expr to prevent expr from evaluating prematurely.
  • Expressions given by DialogProlog are evaluated after symbol values are localized, and before any expression given as the argument of Dialog is evaluated.
Enter a dialog, first printing out the stack:
Return from the dialog:
Click for copyable input
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