Library of Leng + Cycling

[Sage]

With Library of Leng in play, is a player able to discard the cycled card to the top of their library and thus draw said card as a result?

[Taurelin]

No. Library of Leng says: If an effect causes you to discard a card, discard it, but you may put it on top of your library instead of into your graveyard.

In the case of cycling, however, discarding is not part of the effect, it's part of the cost. So Library doesn't apply here.