Source code in the rexx programming language

/*REXX program  reads  a file  and  displays  it to the screen  (with word wrap).       */
parse arg iFID width .                           /*obtain optional arguments from the CL*/
if  iFID=='' |  iFID==","  then  iFID='LAWS.TXT' /*Not specified?  Then use the default.*/
if width=='' | width==","  then width=linesize() /* "      "         "   "   "     "    */
@=                                               /*number of words in the file (so far).*/
            do  while lines(iFID)\==0            /*read from the file until End-Of-File.*/
            @=@ linein(iFID)                     /*get a record  (line of text).        */
            end   /*while*/
$=word(@,1)                                      /*initialize  $  with the first word.  */
            do k=2  for words(@)-1;  x=word(@,k) /*parse until text (@) exhausted.      */
            _=$ x                                /*append it to the  $  list and test.  */
            if length(_)>=width  then do;  say $ /*this word a bridge too far?    > w.  */
                                           _=x   /*assign this word to the next line.   */
                                     end
            $=_                                  /*new words (on a line)  are OK so far.*/
            end   /*m*/
if $\==''  then say $                            /*handle any residual words (overflow).*/
                                                 /*stick a fork in it,  we're all done. */


/*REXX program  reads  a  file  and  displays  it to the screen  (with word wrap).      */
parse arg iFID width kind _ .                    /*obtain optional arguments from the CL*/
if  iFID=='' | iFID==","  then iFID = 'LAWS.TXT' /*Not specified?  Then use the default.*/
if width=='' |width==","  then width= linesize() /* "      "         "   "   "     "    */
if right(width, 1) =='%'  then width= linesize() * translate(width, , "%")  %  100
if kind=='' | kind==","   then kind= 'Left'      /*Default?  Then use the default: LEFT */
just= left(kind, 1);  upper just                 /*use 1st char of JUSTIFY,  uppercased.*/
if pos(just, 'BCLR')==0  then call err "KIND  (3rd arg) is illegal:"      kind
if _\==''                then call err "too many arguments specified."      _
if \datatype(width,'W')  then call err "WIDTH (2nd arg) isn't an integer:"  width
n=0                                              /*the number of words in the file.     */
            do j=0  while lines(iFID)\==0        /*read from the file until End-Of-File.*/
            _=linein(iFID)                       /*get a record  (line of text).        */
                 do  until _=='';      n= n + 1  /*extract some words  (or maybe not).  */
                 parse var _   @.n  _            /*obtain and assign next word in text. */
                 end   /*until*/                 /*parse 'til the line of text is null. */
            end        /*j*/

if j==0   then call err  'file'  iFID  "not found."
if n==0   then call err  'file'  iFID  "is empty  (or has no words)"
$=@.1                                            /*initialize  $  string with first word*/
            do m=2  for n-1;           x= @.m    /*parse until text  (@)  is exhausted. */
            _= $ x                               /*append it to the  $  string and test.*/
            if length(_)>= width  then call tell /*this word a bridge too far?   > w    */
            $= _                                 /*the new words are OK  (so far).      */
            end   /*m*/
call tell                                        /*handle any residual words  (if any). */
exit                                             /*stick a fork in it,  we're all done. */
/*──────────────────────────────────────────────────────────────────────────────────────*/
err:  say;    say '***error***';     say;     say arg(1);     say;      say;       exit 13
/*──────────────────────────────────────────────────────────────────────────────────────*/
tell: if $==''  then return                      /* [↓]  the first word may be too long.*/
      w=max(width, length($) )                   /*don't truncate long words  (> w).    */
            select
            when just=='L'  then $=  strip($)    /*left ◄────────                       */
            when just=='R'  then $=  right($, w) /*──────► right                        */
            when just=='B'  then $=justify($, w) /*◄────both────►                       */
            when just=='C'  then $= center($, w) /*  ◄centered►                         */
            end   /*select*/
      say $                                      /*display the line of words to terminal*/
      _= x                                       /*handle any word overflow.            */
      return                                     /*go back and keep truckin'.           */


/* REXX ***************************************************************
* 20.08.2013 Walter Pachl  "my way"
* 23.08.2013 Walter Pachl changed to use lastpos bif 
**********************************************************************/
Parse Arg w
oid=w'.xxx'; 'erase' oid
Call o left(copies('123456789.',20),w)
s='She should have died hereafter;' ,
  'There would have been a time for such a word.' ,
  'Tomorrow, and tomorrow, and tomorrow, and so on'
Call ow s
Exit
ow:
  Parse Arg s
  s=s' '
  Do While length(s)>w
    i=lastpos(' ',s,w+1) /* instead of loop */
    If i=0 Then
      p=pos(' ',s)
    Else
      p=i
    Call o left(s,p)
    s=substr(s,p+1)
    End
  If s>'' Then
    Call o s
  Return
o:Return lineout(oid,arg(1))