How to store graph in files

Question

I want to store the following information in a file. My program is consisted of set of string that are connected forming a graph. I call each single string "Tag".

let's say we have 3 main tags $Mohammed , $car , $color

Each of the main tags contains sub tags and each sub tag has a value or another sub tag or set of sub tags.

$Mohammad:
    $Age: "18"
    $color: $red
    $kind_of: $human
    $car:
        $type: $toyota
        $color: $blue
        $doors:
            $number: "3"
$car:
    $made_of: $metal
    $used_for: $transporting
    $types: {$mercedes,$toyota,$nissan}
    $best_color: $red

$color:
    $usedto: $coloring_things
    $example: {$red,$green,$blue,...}

But this in not the only thing, there is a connection between the tags of the same name, so that $Mohammed->$car->$color must be connected with the main tag $color. and $Mohammed->$color:$red , $car->$best_color:$red , $color->$best_color: $red and the main tag $red must all be connected to each other.

The tags connected means be stored in a way that I can call the connected tags at once. just like the computer memory. when it calls something from the memory, it calls the information before and after the requested information.

When I looked to my situation in the first time, I thought that XML would solve it, but then I realized that XML can't represent graph.

I don't want to use databases for this. I want to keep database as my last weapon.

Any idea or suggestion about how can I store,connect and recall the informations from my program? Thanks in advance.

Answer 1

Take a loot at boost's property_tree

It contains a nice c++ way to represent your graph, and let's you very easily decide what kind of file-representation you want. Be that xml, json, info.

Also, I don't see why your graph can't be represented by xml, as it supports named nodes.

Although property_tree also supports the ini format, that actually can't represent your >2 level deep tree.