*** strrep.m-2.1.28	Tue May  2 01:39:24 2000
--- strrep.m	Fri May 12 08:21:15 2000
***************
*** 45,70 ****
      t = s;
      return;
    endif
    ind = findstr (s, x, 0);
!   len = length (ind);
!   if (len == 0)
      t = s;
!   else
!     save_empty_list_elements_ok = empty_list_elements_ok;
!     unwind_protect
!       empty_list_elements_ok = 1;
!       l_x = length (x);
!       tmp = s (1 : ind (1) - 1);
!       t = strcat (tmp, y);
!       for k = 1 : len - 1
!         tmp = s (ind (k) + l_x : ind (k+1) - 1);
!         t = strcat (t, tmp, y);
!       endfor
!       tmp = s (ind(len) + l_x : length (s));
!       t = [t, tmp];
!     unwind_protect_cleanup
!       empty_list_elements_ok = save_empty_list_elements_ok;
!     end_unwind_protect
    endif
  
  endfunction
--- 45,94 ----
      t = s;
      return;
    endif
+ 
    ind = findstr (s, x, 0);
!   if (length(ind) == 0)
      t = s;
! 
!   elseif (length(y) > 0)      # replacement
!     ## Copy the parts of s that aren't being replaced.  This is done
!     ## with an index vector, with jumps where each search string
!     ## is found.  For a jump of 0 (target length == replacement length)
!     ## the index is just cumsum ( ones (length (s))).  For non-zero
!     ## jumps, add the jump size to the ones vector at each found position.
!     jump = length(y) - length(x);
!     if (jump > 0)     # s expands
!       di = ones(size(s));
!       di (ind) = 1 + jump * ones (length (ind), 1);
!       t (cumsum (di)) = s;
!       if (size(s,1) == 1)
! 	t = t';
!       endif
!     elseif (jump < 0) # s contracts
!       di = ones (jump * length (ind) + length (s), 1);
!       di (ind + jump * [0:length(ind)-1]) = 1 - jump * ones(length(ind), 1);
!       t = s (cumsum (di));
!     else              # s stays the same length
!       t = s;
!     endif
! 
!     ## Now, substitute a copy of the replacement string whereever the
!     ## search string was found.  Note that we must first update the
!     ## target positions to account for any expansion or contraction
!     ## of s that may have occurred.
!     ind = ind + jump * [ 0 : length (ind) - 1 ];
!     repeat = [1 : length (y)]' * ones (1, length (ind));
!     dest = ones (length (y), 1) * ind + repeat - 1;
!     t (dest) = y (repeat);
! 
!   else                        # deletion
!     ## Build an index vector of all locations where the target was found
!     ## in the search string, and zap them. 
!     t = toascii(s);
!     repeat = [1 : length (x)]' * ones (1, length (ind));
!     delete = ones (length (x), 1) * ind + repeat - 1;
!     t (delete) = [];
!     t = setstr(t);
    endif
  
  endfunction