Re: lua table order?

[Petite Abeille <petite.abeille@...>]

On Apr 5, 2010, at 10:41 PM, Luiz Henrique de Figueiredo wrote:

>> i expected an output order, but it fails ...
> 
> "The order in which the indices are enumerated is not specified"
> http://www.lua.org/manual/5.1/manual.html#pdf-next

And if you want to order your table, you need to sort it somehow, e.g. alphabetically by keys:

local function Sort( aMap )
    local aList = {}
    local anIndex = 1
    
    for aKey, aValue in pairs( aMap ) do
        aList[ #aList + 1 ] = aKey
    end
    
    table.sort( aList )
    
    return function()
        local aKey = aList[ anIndex ]
        local aValue = aMap[ aKey ]
        
        anIndex = anIndex + 1
        
        return aKey, aValue
    end
end


local tb={['one']=989,['two']='zeze',['tree']=78,['four']='joseepti',['five']=os.date('!%a, %d-%b-%Y %H:%M:%S GMT')}

for aKey, aValue in Sort( tb ) do
    print( aKey, aValue )
end

> five	Mon, 05-Apr-2010 00:07:07 GMT
> four	joseepti
> one	989
> tree	78
> two	zeze

Check the wiki for alternatives:

http://lua-users.org/wiki/OrderedTable