JSFiddle - React, Tailwind, and code Playground

JavaScript

function Dictionary(overwrite){
	this.overwrite = overwrite === true;
	var __k = [];
	var __v = [];
	
	this.put = function(key, value){
		if(!this.overwrite || __k.indexOf(key) === -1){
			__k.push(key);
			__v.push(value);
		}
	};
	
	this.get = function(key){
        var idx=__k.indexOf(key);
		if(idx >= 0){
            return __v[idx];
		}
        return null;
	};
    
    
	this.remove = function(key){
		var i = __k.indexOf(key);
		if(i != -1){
			__k.splice(i,1);
			__v.splice(i,1);
		}
    };
	
	this.clearAll = function(value){
		for(var i = 0; i < __v.length; i++){
			if(__v[i] == value){
				__k.splice(i,1);
				__v.splice(i,1);
			}
		}
	};
	
	this.iterate = function(func){
		for(var i = 0; i < __k.length; i++){
			func(__k[i], __v[i]);
		}
	};
	
}


// -- DEMO ---

var dict=new Dictionary(true);
dict.put("myName", "James Bond");
alert("My name is: "+dict.get("myName"));