In A=Range[10^4];?A Out (* definition of A*)
It works for 10^4. But if I increase the number to 10^6
In A=Range[10^6];?A (* Do not try this *)
makes my PC freezed. It is even impossible to abort. The only way out is quitting mathematica without saving documents.
While I was writing this article, I recalled the command
Definition[A] doesn't make such problem.
Then my question was changed. What is advantage/disadvantage of