anchor.diff:      
       REPL.prototype.onNavigateHistory = function(direction) {
           this.previousCommandOffset += direction;
  +        var previousCommands = JSON.parse(localStorage.getItem("previousCommands"));
           
           if(this.previousCommandOffset < 0) {
               this.previousCommandOffset = -1;
  
positive.code:             return;
          }
          
          if(this.previousCommandOffset >= this.previousCommands.length) {
              this.previousCommandOffset = this.previousCommands.length;
              this.setInput("");
              return;
          }
          
          this.setInput(this.previousCommands[this.previousCommandOffset]);
      };
      
      REPL.prototype.onKeyDown = function(ev) {
  
negative.code:     function REPL(index) {
          this.index = index;
          
          var previousCommands = JSON.parse(localStorage.getItem("previousCommands"));
          if(previousCommands === null) {
            localStorage.setItem("previousCommands", JSON.stringify([]));
            previousCommands = []
          }
  
          this.previousCommandOffset = previousCommands.length;
      }
      
      REPL.all = [];
  