This is documentation for Mathematica 6, which was
based on an earlier version of the Wolfram Language.
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initiates a dialog for every expression used in the evaluation of expr.
TraceDialog[expr, form]
initiates a dialog only for expressions which match form.
TraceDialog[expr, s]
initiates dialogs only for expressions whose evaluations use transformation rules associated with the symbol s.
  • The expression to be evaluated when a dialog is called is given as Out[$Line] of the dialog, wrapped in HoldForm. The expression can be seen by asking for % when the dialog is first started.
  • Any value returned from the dialog is discarded.
  • TraceDialog[expr] returns the result of evaluating expr.
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