No Need of loop
var a = {
"fruit" : ["mango","orange"],
"veg" : ["carrot"]
};
var b = [
{ "type" : "fruit" , "pop" : function(){this.name = a[this.type]; delete this.pop; return this} }.pop() ,
{ "type" : "veg" , "pop" : function(){this.name = a[this.type]; delete this.pop; return this} }.pop()
]