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─────Programmer's WorkBench─────────────────────────────────────────────────
 
     PWB provides the fundamental constructs to write loops and to
     control the flow of execution in macros: labels, a 'goto'
     directive, and conditional jumps.
 
     All functions in PWB return a true or false result that can be
     tested. This result generally correspond to success or failure of
     the operation. Use the following directives to test function
     results and define labels:
 
     Syntax        Description
 
     =>[label]     Goto: unconditionally branch to <label>.
     +>[label]     If: branch to <label> on True.
     ->[label]     If not: branch to <label> on False.
     :>label       Define the label <label>.
 
     If the label is omitted in =>, +>, or ->, PWB exits the macro. The
     label in ':>label' is required.
 
     You can write recursive macros to perform iteration, but PWB
     limits the number of nested macro calls to 20. This limit makes
     recursion impractical in most situations.
 
     TIP: Use the following macros to return a result from a macro:
 
          ;  Set True return value (cancels active arguments)
          True := Cancel
 
          ;  Set False return value (turns off Meta prefix)
          False := Meta +>off Meta :>off Meta
 
     See
 
     ◄Macro Conditional Example►
     ◄Macro Looping Examples►
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