Get the index of a particular string in a redis list?
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I have a list container the current players for a game, and I keep track of the current turn with another integer. When a player leaves, I remove them from the players list. However, there are cases where I need to also adjust the turn value (when a player leaves). 

I've found that if the index of a particular player is LESS than the turn value, then I need to decrement the turn variable. For example

    1) A B C(t=2) D E => B leaves
    2) A C(t=1) D E

Since B's index was before turn, turn is decremented. Conversely

    1) A B C(t=2) D E => D leaves
    2) A B C(t=2) E

Here, we do not have to change the turn value, since the player that left is AFTER turn.

So my question is, how can I determine the index of a particular string in a list? (non-blocking). If this is not possible, is there maybe another solution?