This is documentation for Mathematica 8, which was
based on an earlier version of the Wolfram Language.
View current documentation (Version 11.2)

CellProlog

CellProlog
is an option to Cell that gives an expression to evaluate before each ordinary evaluation of the contents of the cell.
  • CellProlog:>expr evaluates expr for every ordinary kernel evaluation done in the cell, as initiated for example by Shift+Enter or by Evaluate in Place.
  • CellProlog is often set at a style or notebook level, rather than for individual cells.
Rules for temporarily setting $Post:
Rules for setting up local package contexts for a cell:
Rules for temporarily setting $Post:
In[1]:=
Click for copyable input
 
Rules for setting up local package contexts for a cell:
In[1]:=
Click for copyable input
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