index
Returns the position of the first element in @queue which contains @data.
Return
the position of the first element in @queue which contains @data, or -1 if no element in @queue contains @data
Since
2.4
Parameters
data
the data to find
Returns the position of the first element in @queue which contains @data.
the position of the first element in @queue which contains @data, or -1 if no element in @queue contains @data
2.4
the data to find