Level 15 (exceptionalCrossing.js)?

Question

I'm stuck on Level 15 of Untrusted.

I've gotten this far with no actual knowledge of Javascript beyond knowing C and assuming things are the same. I see no possible solution to this puzzle without some trick of the language I don't know about- no matter what I put in there, player.killedBy() is going to be called, and the Professor is going to die.

Any hints?

Answer 1

You can put anything in there that doesn't exist. eg

player.killedBy(nothing);

When you go in the water it will then throw an error message because nothing doesn't exist.

Answer 2

Actually you can pass the level without throwing any exception, just hacking the code:

[line 32] player.killedBy('
');},'onCollision':function(player){map.getWidth(
);

Just replacing the "onCollision" action again with a function that doesn't do anything.

Then you can walk on water!!

Answer 3

You can use concatenation and short circuit the collision detection routine i.e.

map.defineObject('water', {
    'symbol': '░',
    'color': '#44f',
    'onCollision': function (player) {
        player.killedBy(''+map.placePlayer(1,1));
    }
});

Answer 4

Of course, the hint is in the name.

You've got to throw an exception.

Answer 5

I like this way:

player.killedBy(function() { throw 'I am Jesus';} ());

Answer 6

You can't acrossing water, but you can pick it up.

map.defineObject('water', {
        'symbol': '░',
        'color': '#44f',
        'onCollision': function (player) {
            player.killedBy();},'type':'item','beha':function(me){me.move('up');
        }
    });

Answer 7

also u can use infinite recursion..

player.killedBy((function(){x=function(){x();};x();})());