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  With LOCALs and STATICs:

  A limitation imposed by the macro compiler in Clipper prevents Mach SIx
  from using LOCAL and STATIC variables as portions of an expression.

  As you may have noticed from perusing the Mach SIx header file,
  MACHSIX.CH, Mach SIx functions receive both character and block forms of
  the FOR condition for all optimizable commands.  Since there is no way to
  internally de-compile a code block, Mach SIx evaluates queries solely
  from the string copy of the FOR condition.

  Each condition in the query is evaluated separately; indexed conditions
  first, non-indexed second.  The problem becomes evident when a string
  containing LOCALs or STATICs is macro compiled from deep within the Mach
  SIx code and those variables are no longer in scope.  (The code block
  form of the condition is only used when Mach SIx cannot optimize the
  expression and control is transferred to Clipper.)

  You can work around this limitation by manually creating a string
  condition and calling the desired optimizable command with the condition
  as an extended expression.  The following are several examples using
  character, number, and date query conditions.

     #include "SIXCDX.CH"
     #include "MACHSIX.CH"

     LOCAL cState, nAge, dDate, cCond1, cCond2, cCond3, nCount

     //............................................ STATE = 'CA'
     cState := 'CA'
     cCond1 := "STATE=='" + cState + "'"
     COUNT TO nCount FOR ( cCond1 )
     ? "Poof!"
     ? nCount

     //............................................... AGE < 30
     nAge = 30
     cCond2 := 'AGE < ' + alltrim( str ( nAge ) )
     COUNT TO nCount FOR ( cCond2 )
     ? "Poof!"
     ? nCount

     //............................. HIREDATE = ctod('04/01/93')
     dDate = ctod("04/01/93")
     cCond3 := "HireDate = ctod('" + dtoc( dDate ) + "')"
     COUNT TO nCount FOR ( cCond3 )
     ? "Poof!"
     ? nCount

     //............................STATE == 'CA' .AND.  AGE < 30
     COUNT TO nCount FOR ( cCond1 + " .AND. " + cCond2 )
     ? "Poof!"
     ? nCount