#
#  SearchAllString 
#
#  Wrapper for SearchString that returns the position of all occurances
#  of a patterns in a string. Also a variant when we allow for one or
#  several mismatches.
#
#                                       Alexander Roth (Nov 3, 2005)
#

SearchAllString := proc(pat:string, txt:string) -> list;
  ret := [];
  do
    if length(ret)=0 then 
      a := SearchString(pat, txt);
      if a=-1 then break fi;
      where := a;
    else
      a := SearchString(pat, txt[where+2..-1]);
      if a=-1 then break fi;
      where := where+a+1;
    fi;
    # the "+1" to indicate the first char in pattern
    ret := append(ret, where+1);
  od;
  return(ret);
end:

HammingSearchAllString := proc(pat:string, txt:string; d=1:posint) -> list;
  ret := [];
  do
    if length(ret)=0 then
      a := HammingSearchString(pat, txt, d);
      if a=-1 then break fi;
      where := a;
    else
      a := HammingSearchString(pat, txt[where+2..-1], d);
      if a=-1 then break fi;
      where := where+a+1;
    fi;
    ret := append(ret, where+1);
  od;
  return(ret);
end: