User can make duplicate cards

[svmi3195]

I can add duplicates of existing cards (with same q and a)

[Anton Tymczenko]

I wouldn't put tests for this issue on each input (q/a) change, but it would be great to have somewhere at this page a button "check for duplicates"

[svmi3195]

Or maybe "remove duplicates" to auto remove them instantly?

Also, if we really don't want duplicates we could use Sets to keep collections.

[Anton Tymczenko]

I've never heard of Sets, but took a look at this stuff at MDN:

var mySet = new Set();

mySet.add(1); // Set [ 1 ]
mySet.add(5); // Set [ 1, 5 ]
mySet.add(5); // Set [ 1, 5 ]
mySet.add('some text'); // Set [ 1, 5, 'some text' ]
var o = {a: 1, b: 2};
mySet.add(o);

mySet.add({a: 1, b: 2}); // o is referencing a different object so this is okay

so you really can add duplicate object to Set anyway :(

and yes, it should be "remove duplicates" button

[svmi3195]

Ah right, it doesn't go deep to compare object's properties. Will have to iterate through the collections then.