Hash Object vs Array Order

I needed to verify that values were in the order specified by a user in a dual selector control object contained in a SAS/AF frame.

My first thought was to load the selected values into a hash object then use a hash iterator object to spin thru the data using its .first() and .next() methods. That worked, but not as I would have expected. The values were all there but they were not in the order entered (natural order) of C, A, D, B but rather in this order: A, C, B, D.

The ordered: 'a' | 'd' (ascending or descending) attribute of the hash declaration would not work in this scenario so I ended up using a one dimensional _temporary_ array. See the below source code and output to better understand what I am describing.

data loadthis ( keep = valx ) ;

  infile datalines eof = alldone ; 

    input valx $ @@ ;

    n + 1 ;

    output ;

  return ;

  alldone:

    call symputx( 'acnt', n ) ;

  return ;

  datalines ;

C A D B 

;

run ;

data out_array 

     out_hiter ;

  if 0 then set loadthis /* prime the PDV */;

  keep valx ;

  /* load hash object and hash iterator object */

  declare hash h(dataset:'loadthis') ;

  declare hiter hi( 'h' ) ;

  h.definekey( 'valx' ) ;

  h.definedone() ;

  /* dimension and populate array */

  array aval[ &acnt ] $ _temporary_ ;

  do until ( eof ) ;

    set loadthis end = eof ;

    rc + 1 ;

    aval[ rc ] = valx ;

  end ;

  /* output array */

  do rc = 1 to &acnt ;

    valx = aval[ rc ] ;

    output out_array ;

  end ;

  /* output hash object and hash iterator object */

  rc = h.output( dataset:'out_hash' ) ;

  rc = hi.first() ;

  do while( rc = 0 ) ;

    output out_hiter ;

    rc = hi.next() ;

  end ;

  stop ;

run ;

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