Finding the first position in a list that is over a certain value

Let's say I have the following list:

L = {2,4,6,8,10}

How can I get Mathematica to find the index position of the first value in the list that is over 4 (6 in this case). I tried Position[L, L > 4], but this gave no output. Any help would be appreciated.

Answer

In version 10 there is a new function FirstPosition:

L = {2, 4, 6, 8, 10};

FirstPosition[ L, x_ /; x > 4]

{3}

The second argument of Position as welll as of FirstPosition is a pattern, so this would yield what you seemed to expect:

Position[ L, x_ /; x > 4]

{{3}, {4}, {5}}

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