;~ http://www.autohotkey.com/board/topic/93300-what-format-to-store-settings-in/#entry588268  
json = {"version":"1","window":{"state":3,"screenX":25,"screenY":25,"width":790,"height":605,"test":{"nested":"object"}},"sidebar":{"visible":false,"width":"200"}}  
j := parseJson(json)  
MsgBox % j.version  
MsgBox % j.window.screenY  
return   
parseJson(jsonStr){  
    SC := ComObjCreate("ScriptControl")   
    SC.Language := "JScript"  
    ComObjError(false)  
    jsCode =  
    (  
    function arrangeForAhkTraversing(obj){  
        if(obj instanceof Array){  
            for(var i=0 ; i<obj.length ; ++i)  
                obj[i] = arrangeForAhkTraversing(obj[i]) ;  
            return ['array',obj] ;  
        }else if(obj instanceof Object){  
            var keys = [], values = [] ;  
            for(var key in obj){  
                keys.push(key) ;  
                values.push(arrangeForAhkTraversing(obj[key])) ;  
            }  
            return ['object',[keys,values]] ;  
        }else  
            return [typeof obj,obj] ;  
    }  
    )  
    SC.ExecuteStatement(jsCode "; obj=" jsonStr)  
    return convertJScriptObjToAhks( SC.Eval("arrangeForAhkTraversing(obj)") )  
}  
 
convertJScriptObjToAhks(jsObj){  
    if(jsObj[0]="object"){  
        obj := {}, keys := jsObj[1][0], values := jsObj[1][1]  
        loop % keys.length  
            obj[keys[A_INDEX-1]] := convertJScriptObjToAhks( values[A_INDEX-1] )  
        return obj  
    }else if(jsObj[0]="array"){  
        array := []  
        loop % jsObj[1].length  
            array.insert(convertJScriptObjToAhks( jsObj[1][A_INDEX-1] ))  
        return array  
    }else  
        return jsObj[1]  
}

string={hello:'world',its:{over:9000},foo:['bar']}  
msgbox,% jsonGet(string,"hello")  
msgbox,% jsonGet(string,"its.over")  
msgbox,% jsonGet(string,"foo[0]")   
obj:={hello:"world",its:{over:9000},foo:["bar"]}  
msgbox,% jsonBuild(obj)   
string={hello:'world',its:{over:9000},foo:['bar']}  
obj:=jsonAHK(string)  
msgbox,% obj.hello  
msgbox,% obj.its.over  
msgbox,% obj.foo.0   
jsonAHK(s){  
    static o:=comobjcreate("scriptcontrol")  
    o.language:="jscript"  
    return o.eval("(" s ")")  
}  
jsonBuild(j) {   
    for x,y in j  
        s.=((a:=(j.setcapacity(0)=(j.maxindex()-j.minindex()+1)))?"":x ":")(isobject(y)?jsonBuild(y):y/y||y==0?y:"'" y "'") ","   
        ;s.=x ":" (isobject(y)?jsonBuild(y):y/y||y==0?y:"'" y "'") ","  
    return (a?"[" rtrim(s,",") "]":"{" rtrim(s,",") "}")  
    ;return ("{" rtrim(s,",") "}")  
}  
jsonGet(s,k){  
    static o:=comobjcreate("scriptcontrol")  
    o.language:="jscript"  
    return o.eval("(" s ")." k)  
}