5 List Example

ORIGIN '~beta/containers/list';  
--- program:descriptor ---
(* This demo program illustrates the usage of the list pattern.  The first
 * part of the demo illustrates inserting and deleting elements from the lists.
 * 
 * At the end of this file, a copy of the output of this program is given
 *)
(# intList: list(# element:: integerObject #);
   
   intList1, intList2: @intList; intList3: ^intList;
   i: [10]^integerObject;
   listPosition: ^intList.theCellType;
   
do (* initializing the integerObjects *)
   (for int:10 repeat &integerObject[]->i[int][]; int->i[int] for);
   
   (* initializing intList1 and putting some integerObjects into it *)
   intList1.init;
   'intList1.prepend: '->puttext;
   (for int:4 repeat
      i[int][]->intList1.prepend
   for);
   intList1.scan(# do current->putint; ','->put #); newline;
   
   (* initializing intList3 and putting some integerObjects into it *)
   intList2.init;
   'intList2.append: '->puttext;
   (for int:4 repeat 
      i[int+3][]->intList2.append
   for);
   intList2.scan(# do current->putint; ','->put #); newline;
   
   (* illustrates the reverse scanning *)
   'intList2.scanReverse: '->puttext;
   intList2.scanReverse(# do current->putint; ','->put #); newline;
   
   (* initializing intList3 *)
   &intList[]->intList3[]; intList3.init;
   
   (* illustrating concatenation of lists *)
   'intList1[]->intList2.concatenate->intList3[]: '->puttext;
   intList1[]->intList2.concatenate->intList3[];
   intList3.scan(# do current->putint; ','->put #); newline;
   
   (* illustration getting the position of some integerObject in the list, and
    * replacing the element at that position
    *)
   '"10"->("2"->intList3.at).elm[]: '->puttext;
   i[2][]->intList3.at->listPosition[];
   i[10][]->listPosition.elm[];
   intList3.scan(# do current->putint; ','->put #); newline;
   
   (* illustrates deleting an element from the list *)
   '6->intList2.at->intList2.delete: '->puttext;
   i[6][]->intList2.at->intList2.delete;
   intList2.scan(# do current->putint; ','->put #); newline;

    i[7][]->intList3.at->listPosition[];
  (* illustrating inserting integerObjects before some list position *)
   '(8,7)->intList3.insertBefore: '->puttext; 
   (i[8][],listPosition[])->intList3.insertBefore;
   intList3.scan(# do current->putint; ','->put #); newline;
                           
   (* illustrating deleting integerObjects after some list position *)
   '7->intList3.deleteAfter: '->puttext; 
   listPosition[]->intList3.deleteAfter;
   intList3.scan(# do current->putint; ','->put #); newline;
   
   (*********** OUTPUT ***************
    * intList1.prepend: 4,3,2,1,
    * intList2.append: 4,5,6,7,
    * intList2.scanReverse: 7,6,5,4,
    * intList1[]->intList2.concatenate->intList3[]: 4,5,6,7,4,3,2,1,
    * "10"->("2"->intList3.at).elm[]: 4,5,6,7,4,3,10,1,
    * 6->intList2.at->intList2.delete: 4,5,7,
    * (8,7)->intList3.insertBefore: 4,5,6,8,7,4,3,10,1,
    * 7->intList3.deleteAfter: 4,5,6,8,7,3,10,1,
    ******************************)
#)


Container Libraries - Reference Manual
© 1992-2002 Mjølner Informatics
[Modified: Thursday October 19th 2000 at 12:51]