local program = [[
    = [What is] February = 
        [February is] a syntax front end for nova , designed around streaming tokens . 
    = = =

    ~ [Many Rules] Many Delimiter ~
        [February can] let you switch between them on the fly .
    ~ ~ ~

    *** [A note] *** 
        SAYS you don't need those [backets] .
        BUT they might help with clarity
    
    *** *** [What is] February
    *** *** ***
]]
local stream = program:gmatch(".")
local char, rule, rule_symbol, label_symbol, depth, symbol, side
local tuple, rules, LEFT, RIGHT = {}, {}, 1, 2
repeat
    rule_symbol, char = "", stream()
    side, rule = LEFT, {{}, {}}
    while char and char:match("[%s%.,]") do
        char = stream()
    end
    if char == nil then
        break
    elseif char == "[" then
        depth, char = 1, stream()
        while char do
            if char == "[" then depth = depth + 1 end
            if char == "]" then depth = depth - 1 end
            if depth == 0  then break             end
            rule_symbol, char = rule_symbol .. char, stream()
        end
    else
        rule_symbol = "" while char and not char:match("%s") do
            rule_symbol, char = rule_symbol .. char, stream() if char == "[" then
                io.stderr:write "Warning: symbol contains `[`. A space may be missing?"
            end
        end
    end
    repeat
        char = stream()
        while char and (char:match("[%s]") or not label_symbol and char:match("[%.,]")) do
            char = stream()
        end
        if not char then
            if label_symbol then
                table.insert(rule[side], {label_symbol, tuple})
            end
            break
        end
        if char:match("[%.,]") then
            symbol = char
        elseif char == "[" then
            symbol, depth, char = "", 1, stream() while char do
                if char == "[" then depth = depth + 1 end
                if char == "]" then depth = depth - 1 end
                if depth == 0  then break             end
                symbol, char = symbol .. char, stream()
            end
        else
            symbol = "" while char and not char:match("%s") do
                symbol, char = symbol .. char, stream() if char == "[" then
                    io.stderr:write "Warning: symbol contains `[`. A space may be missing?"
                end
            end
        end
        if symbol == "," then
            table.insert(rule[side], {label_symbol, tuple})
            tuple = {}
        elseif symbol == "." then
            table.insert(rule[side], {label_symbol, tuple})
            tuple, label_symbol = {}, nil
        elseif symbol == rule_symbol and side == RIGHT then
            if label_symbol then
                table.insert(rule[side], {label_symbol, tuple})
                tuple = {}
            end
            if #rule[LEFT] == 0 and #rule[RIGHT] == 0 then
                break
            else
                table.insert(rules, rule)
                side, rule, label_symbol = LEFT, {{}, {}}, nil
            end
        elseif symbol == rule_symbol and side == LEFT then
            if label_symbol then
                table.insert(rule[side], {label_symbol, tuple})
            end
            tuple, side, label_symbol = {}, RIGHT, nil
        elseif not label_symbol then
            label_symbol = symbol
        else
            table.insert(tuple, symbol)
        end
    until not char
    if #rule[LEFT] ~= 0 or #rule[RIGHT] ~= 0 then
        table.insert(rules, rule)
    end
until not char