The Developer Connection…ice Driver Kit for OS/2 3/DEV3-D1.ISO/devtools/dataflex/for_all.pkg

Text File | 1993-08-10 | 5.6 KB | 208 lines

//************************************************************************
//
// Copyright 1987-1992 Data Access Corporation, Miami FL, USA
// All Rights reserved
// DataFlex is a registered trademark of Data Access Corporation.
//
//
//     $Source: /u3/source.30/product/pkg/RCS/for_all.pkg,v $
//     $Revision: 1.1 $
//     $State: Exp $
//     $Author: james $
//     $Date: 1992/09/08 14:43:05 $
//     $Locker:  $
//
//     $Log: for_all.pkg,v $
//Revision 1.1  1992/09/08  14:43:05  james
//Initial revision
//
//Revision 1.4  92/05/14  16:49:32  SWM
//Updated Copyright slug.
//
//Revision 1.3  92/03/09  19:02:09  james
//Added #CHKSUB directive to insure source
//only compiled with correct revision of
//compiler.
//
//Revision 1.2  92/02/18  20:04:39  steve-l
//altered main command to permit use of file.field instead of index.#
//
//Revision 1.1  91/10/23  10:20:51  elsa
//Initial revision
//
//************************************************************************/

//************************************************************************
//     File Name: For_All.Pkg
// Creation Date: January 1, 1991
// Modified Date: May 23, 1991
//     Author(s): Steven A. Lowe
//
// This module contains the command definitions for the FOR_ALL construct.
//
// FOR_ALL is used to select and process a set of records in a database file;
// FOR_ALL constructs may be nested. FOR_ALL is intended to work in
// conjunction with constraint-clauses.
//
// SYNTAX:
//
//  For_All <File> BY|DOWN <Index> {AS QUE|QUEUE} {DO}
//    <Constraints...>
//    {DO}
//      <loop body>
//  End_For_All
//
// This set of macros implements a constraint-oriented file enumeration
// syntax.  For example, to list all Customers by name in reverse order:
//
//   For_All Customer DOWN Customer.Customer_Name DO
//     showln "Customer: " Customer.RecNum "  " Customer.Customer_Name
//   End_For_All
//
// To list only Customers with a Balance greater than their credit limit:
//
//   For_All Customer BY Index.1
//     CONSTRAIN Customer.Balance GT Customer.Credit_Limit
//     DO
//       showln "Customer: " Customer.RecNum "  " Customer.Customer_Name
//   End_For_All
//
// Constraint clauses are:
//
//   CONSTRAIN <File> RELATES TO <File> ...
//   CONSTRAIN <File> AS <Expression>
//   CONSTRAIN <File.Field> AS <Expression>
//   CONSTRAIN <File.Field> BETWEEN <lowBound> AND <highBound>
//
// For example, to list all customers with a bad status whose names start
// with "A" and which have not made a payment in thirty days:
//
//    For_All Customer BY Index.2       //Index.2 = <Status>+<Name>
//      CONSTRAIN Customer.Status EQ BAD
//      CONSTRAIN Customer.Customer_Name GE "A"
//      CONSTRAIN Customer.Customer_Name LT "B"
//      CONSTRAIN Customer.Last_Pymt_Date LE (Today - 30)
//      DO
//        showln "Customer: " Customer.RecNum "  " Customer.Customer_Name
//    End_For_All
//
//************************************************************************/

#CHKSUB 1 1 // Verify the UI subsystem.

#COMMAND For_All TR "BY""DOWN" R """DO""AS" """AS""QUE""QUEUE" """DO""QUE""QUEUE" .
  #CHECK !1.RECNUM   //must be a file
  #PUSH !u
  #SET U$ !a
  #IFCLASS !3 "F"
    integer FldNdx!uForAll       //make integer to hold index for field
    #SET Q$ !1.RECNUM
    !A [] $82 |CI!q FILENUMBER
    #SET Q$ %!3                  //get field number
    !A [] $82 !3 FIELDNUMBER
    !A [] $345 FILENUMBER FldNdx!uForAll //FIELD_DEF command to set index int
  #ENDIF
  goto EP#!uINVOKE   //start loop
  #IFSAME !4 DO
  #ELSE
    #IFSAME !6 DO
    #ELSE
      MAKEDEF$ FAC!u.X
    #ENDIF
  #ENDIF
  #IFSAME !4 AS
    MAKEDEF$ FAQ!u.X
  #ELSE
    #IFSAME !5 AS
      MAKEDEF$ FAQ!u.X
    #ENDIF
  #ENDIF
  #IFDEF FAQ!u.X
  #ELSE
EP#!uNEXT:
    Constraint_Set (|CI!u * -1)
    #IFSAME !2 BY
      #IFCLASS !3 "F"
        Constrained_Find GT !1 by FldNdx!uForAll
      #ELSE
        Constrained_Find GT !1 by !3
      #ENDIF
    #ELSE
      #IFCLASS !3 "F"
        Constrained_Find LT !1 by FldNdx!uForAll
      #ELSE
        Constrained_Find LT !1 by !3
      #ENDIF
    #ENDIF
return
  #ENDIF
EP#!uFIRST:
  Constraint_Set (|CI!u * -1)
  #IFSAME !2 BY
    #IFCLASS !3 "F"
      Constrained_Find FIRST !1 by FldNdx!uForAll
    #ELSE
      Constrained_Find FIRST !1 by !3
    #ENDIF
  #ELSE
    #IFCLASS !3 "F"
      Constrained_Find LAST !1 by FldNdx!uForAll
    #ELSE
      Constrained_Find LAST !1 by !3
    #ENDIF
  #ENDIF
return
EP#!uINVOKE:
  Constraint_Set (|CI!u * -1) CLEAR
  #IFDEF FAC!u.X
    gosub EP#!uCONSTRAIN           //initialize constraint set
  #ENDIF
  gosub EP#!uFIRST
EP#!uNVKL:
  indicate CONTINUE TRUE
  [FOUND CONTINUE] begin
    gosub EP#!uPROCESS
    #IFDEF  FAQ!u.X                //if AS QUEUE|QUE,
      [CONTINUE] gosub EP#!uFIRST  //find next queue element
    #ELSE                          //else
      [CONTINUE] gosub EP#!uNEXT   //find next set element
    #ENDIF
    [CONTINUE] goto EP#!uNVKL      //loop
  end
  goto EFA!u                       //exit past loop body
  #IFDEF FAC!u.X
EP#!uCONSTRAIN:
  #ELSE
EP#!uPROCESS:
  #ENDIF
#ENDCOMMAND

//
//DO
//
//This command starts the loop process body when constraints are used;
//If no constraints are required, DO should be specified on the FOR_ALL
//command line, and not on a line by itself
//
#COMMAND Do
  #IFDEF EP#!uCONSTRAIN
return
  #ENDIF
EP#!uPROCESS:
  #IF (!0>0)
    !1 !2 !3 !4 !5 !6 !7 !8 !9
  #ENDIF
#ENDCOMMAND

//
//END_FOR_ALL
//
//Ends a For_All loop
//
#COMMAND End_For_All .
return
EFA!u:
  #POP U$
#ENDCOMMAND