Module:OrderedPairs

--[[ Ordered table iterator, allow to iterate on the natural order of the keys of a table.

Example: ]]

function __genOrderedIndex( t ) local orderedIndex = {} for key in pairs(t) do       table.insert( orderedIndex, key ) end table.sort( orderedIndex ) return orderedIndex end

function orderedNext(t, state) -- Equivalent of the next function, but returns the keys in the alphabetic -- order. We use a temporary ordered key table that is stored in the -- table being iterated.

key = nil --print("orderedNext: state = "..tostring(state) ) if state == nil then -- the first time, generate the index t.__orderedIndex = __genOrderedIndex( t ) key = t.__orderedIndex[1] else -- fetch the next value for i = 1,table.getn(t.__orderedIndex) do           if t.__orderedIndex[i] == state then key = t.__orderedIndex[i+1] end end end

if key then return key, t[key] end

-- no more value to return, cleanup t.__orderedIndex = nil return end

function orderedPairs(t) -- Equivalent of the pairs function on tables. Allows to iterate -- in order return orderedNext, t, nil end