Module:String to array

Documentation for this module may be created at Module:String to array/doc

local p = {}


function  string_to_array(Input_String, Separator)

  local my_log ={}

  if type(Input_String) ~= "string" then

    return nil
  end
     
  if type(Separator) ~= "string" then

    return nil
  end


 

  -- find the position of each separator in Input_String:
  local separator_positions = {}
  local next_start_position = 1
  while next_start_position <= #Input_String do
    ch1, ch2 = mw.ustring.find(Input_String, Separator, next_start_position)
    if ch1 ~= nil then
      table.insert(separator_positions, {ch1, ch2})
      next_start_position = ch2 + 1
    else
      next_start_position = #Input_String + 1
    end
    
  end

-- To find the separated substrings, we need to group the beginning position of each Separator with the ending position
-- of the Separator that precedes it, so that we can extract the substring between them. For the first separator, the ending position of the 
-- "preceding separator" is the beginning of the string. The last substring is bounded by the end of the string.
-- 
-- 
endchar = #Input_String
-- We are going to use a "for" statement to loop through the subtables of the separator_positions table. 
count = 0
for i in ipairs(separator_positions) do
    count = count + 1
end
-- 
substring_positions = {}
substring_positions[1] = {1, separator_positions[1][1] - 1}
for i = 2, count do
-- we should check that the table elements are not nil before attempting the assignment
    if separator_positions[i][1] == nil then
        -- report 
    elseif separator_positions[i - 1][2] == nil then 
        -- report
    else
    substring_positions[i] =  {separator_positions[i - 1][2] + 1, separator_positions[i][1] - 1}
    end
end
substring_positions[count + 1] = {separator_positions[count][2] + 1, endchar}

substrings = {}

for i, v in ipairs(substring_positions) do
    substrings[i] = mw.ustring.sub(Input_String, v[1], v[2])
end

  return substrings

end




return p