$btoken(&input,N,C,[&output])

alias btokentest {
  var %range $1
  var %chars $2
  var %string $3

  bset -t &data -1 %string

  var %x $btoken(&data,%range,%chars,$iif($4,$4))

  if ($4) + $bvar($4,1,$bvar($4,0)).text
  else + %x

}

alias btoken {
  hinc -m BTOKEN NUMBER

  var %htable BTOKEN $+ $hget(BTOKEN,NUMBER)

  hadd -m %htable COUNT 0

  var %bvar $1
  var %tokenSeperator $iif($3,$3,$chr(32))

  var %numtok $bnumtok(%bvar, %htable, %tokenSeperator)

  $iif($2 == 0,return %numtok)

  var %range $parseRange($2, %numtok)

  var %startTok $token(%range,1,32)
  var %endTok $iif($token(%range,2,32) >= %startTok,$v1 + 1, $v1 - 1)

  var %temp &t $+ %htable,%return

  while %startTok != %endTok {
    ;var %data $hget(%htable,$iif(%startTok > 0,%startTok, $calc(%numtok + %startTok + 1)),%temp)
    var %data $hget(%htable,%startTok,%temp)
    if ($4) {
      bcopy $4 -1 %temp 1 %data
      bset -t $4 -1 %tokenSeperator

      inc %return %data
      inc %return $len(%tokenSeperator)

      bunset %temp
    }
    else {
      var %return $+(%return,$bvar(%temp,1,%data).text,%tokenSeperator)
    }

    $iif(%startTok > %endTok,dec,inc) %startTok
  }

  hfree %htable
  return $iif($4,$calc(%return - $len(%tokenSeperator)),$left(%return,- $+ $len(%tokenSeperator)))
}

alias bnumtok {

  var %bvar $1
  var %htable $$2

  var %btoksep &btoksep $+ %htable
  var %bnumtok &bnumtok $+ %htable

  var %toksep $iif($3,$3,$chr(32))

  bset %btoksep -1 $asc(%toksep)
  $iif($right(%toksep,-1),bset -t %btoksep -1 $v1)

  $iif($hget(%htable,COUNT) != 0,return $hget(%htable,COUNT))
  var %findPos 1
  var %lastFindPos 1

  var %lengthOfBvar $bvar(%bvar,0)

  var %odd $bvar(%btoksep,0)

  while %lastFindPos < %lengthOfBvar {
    var %findPos $iif($bfind(%bvar,%lastFindPos,$bvar(%btoksep,1,$bvar(%btoksep,0))) == 0,$bvar(%bvar,0),$v1) - 1

    hinc -m %htable COUNT

    bcopy %bnumtok 1 %bvar %lastFindPos $calc(%findpos - %lastFindPos + $iif($calc(%findPos + %odd + 1) > %lengthOfBvar,2,1))

    hadd -mb %htable $hget(%htable,COUNT) %bnumtok

    bunset %bnumtok

    var %lastFindPos $calc(%findPos + %odd + 1)
  }

  return $hget(%htable,COUNT)
}

alias parserange {
  var %input $1
  var %maxRange $2

  var %startNumber
  var %endNumber

  ;if the first character is a -, the first parameter is a negative number; proceed to second - or end of the string
  var %flag $iif($left(%input,1) == -,$true,$fale)

  var %b $token(%input,1,45)

  var %input $iif(%flag,$right(%input,-1),%input)
  var %a $pos(%input,-,1)

  if %a == $len(%input) {
    ;second - as at end of string (range encountered) no second integer
    %startNumber = $iif(%flag,$calc(%maxRange - %b + 1),%b )
    %endNumber = %maxRange
  }
  else if !%a {
    ;no - after the first token; no range
    %startNumber = %b
    %endNumber = %startNumber
  }
  else {
    ;range encountered; second number present
    var %startNumber $iif(%flag,$calc(%maxRange - %b + 1),%b)

    ;proceed to first - or end of string, and if there is a positive or negative integer

    var %a $iif($Pos(%input,-,1),$v1,0)
    var %b $iif($pos(%input,-,2),$v1,0)

    if %b > 0 && $calc(%b - %a) == 1 {
      ;second integer is negative,
      var %endNumber $calc(%maxRange - $token(%input,2,45) + 1)
    }
    else if %b == 0 {
      ;second integer is positive
      var %endnumber $token(%input,2,45)
    }
    else {
      ;unknown condition
      var %endnumber $token(%input,2,45)
    }
  }
  return %startNumber %endNumber
}

alias -l + {
  if (!$window(@DEBUG)) window -e @DEBUG
  echo @DEBUG $1-
}
alias -l - {
  noop
  }urn %start %end
}