test.json

{
        "name":"Regexp",
        "data":["entry_rule"],
        "entry_rule" : "alg","children" : [
            
       {
        "name":"Rule",
        "data":["rule_name"],
        "rule_name" : "alg",
        "children" : [
          
       {
        "name":"Possibility",
        "data":["val"],
        "val" : "must","children" : [
            
       {
        "name":"Body",
        "data":["position"],
        "position" : "start with",
        "children":[
          
       {
        "name":"Quantifier",
        "data":["val"],
        "val" : ""
        }
     ,
          
       {
        "name":"Literal",
        "data":["val"],
        "val" : "toto"
        }
     
          ]
        }
     
        ]}
        ]
        }
     
        ]}