TBColumn -- Overview
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 Class Function

 TBColumnNew()   Create a new TBColumn object
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 Exported Instance Variables

 block           Code block to retrieve data for the column
 cargo           User-definable variable
 colorBlock      Code block that determines color of data items
 colSep          Column separator character
 defColor        Array of numeric indexes into the color table
 footing         Column footing
 footSep         Footing separator character
 heading         Column heading
 headSep         Heading separator character
 picture         Character string controlling column formatting and editing
 postBlock       Code block validating values
 preBlock        Code block determining editing
 width           Column display width
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 Exported Methods

 setstyle()      Maintains dictionary within object