on str_replace (stringToFind, stringToInsert, input)

  output = ""

  findLen = stringToFind.length - 1

  repeat while true

    currOffset = offset(stringToFind, input)

    if currOffset=0 then exit repeat

    put input.char [1..currOffset] after output

    delete the last char of output

    put stringToInsert after output

    delete input.char [1.. (currOffset + findLen)]

  end repeat

  put input after output

  return output

end