关于lists:member 与 sets:is_element 性能比较

1> L = lists:seq(1,100000).
[1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,
23,24,25,26,27,28,29|...]
2> Fun1 = fun (X) -> lists:member(X, L) end.
#Fun<erl_eval.6.13229925>
3> Fun2 = fun (X) -> S = sets:from_list(L), sets:is_element(X, S) end.
#Fun<erl_eval.6.13229925>
4> timer:tc(Fun1,50000).
{3,
{'EXIT',{undef,[{timer,tc,2},
{erl_eval,do_apply,5},
{shell,exprs,7},
{shell,eval_exprs,7},
{shell,eval_loop,3}]}}}
5> timer:tc(Fun1,[50000]).
{175,true}
6> timer:tc(Fun2,[50000]).
{518784,true}
7>