Conditional moves illegal?

I was thinking about the conditional moves we can make at chess.com & I wonder if they are against the rules of chess. 

It all depends on how they've been programmed by Erik & co but imagine a situation where your opponent's next move would result in a draw by repetition.  You set up a conditional move saying that if they make that move, then you do a certain other move (different to the one you've already done 3 times).  I wonder what will happen - if the system allows your conditional move then it's illegal.  Maybe Erik or one of his colleagues can answer?  Perhaps others have thoughts on this?

(Incidentally I'm not arguing against conditional moves - they're a great feature.)

The conditional move is not illegal. You have to claim a draw.

FIDE rules: http://www.fide.com/component/handbook/?id=124&view=article

"9.2 The game is drawn upon a correct claim by the player having the move, when the same position, for at least the third time (not necessarily by a repetition of moves):

a. is about to appear, if he first writes his move on his scoresheet and declares to the arbiter his intention to make this move, or

b. has just appeared, and the player claiming the draw has the move.

Positions as in (a) and (b) are considered the same, if the same player has the move, pieces of the same kind and colour occupy the same squares, and the possible moves of all the pieces of both players are the same.
Positions are not the same if a pawn that could have been captured en passant can no longer be captured in this manner. When a king or a rook is forced to move, it will lose its castling rights, if any, only after it is moved."

I believe rather than option a, a player on the site can claim a draw after his move causes the same position to appear three times. Due to the conditional move the would-be claimant does not have a chance to hit the draw button. Now the would-be claimant has to wait for option b.

yes indeed!

sounds very theoretically though ... but interesting

I can see the potential for a conditional move to deny a player the opportunity to claim the draw on repetition immediately after their move, but if the player wanted to avoid the draw by repetition couldn't they just have deviated in the same way on one of the prior repetitions?

Something like a "claim draw immediately after move" checkbox would address this, however I'd imagine it happens so infrequently that it's really not an issue.

Hmmm - I didn't realise that a draw had to be claimed.  But I'm sure that I played a game recently when the game was declared a draw by chess.com after 3 identical moves.

Maybe I'm wrong ... thanks for the comments anyway folks

 Maybe your opponent claimed the draw right after you made your move?

You're right - that must have been it