Perl Study Notes No. 3

1. A given expression has different meanings in different contexts
2. In the scalar context, Nums returns the number of its elements. In the list context, its elements are returned.
3. Print @ Nums; each element is not separated by spaces unless print "@ Nums ";
4. Print Nums; it is directly used as a list, not a scalar
5. If a scalar expression is used in the list context, it will convert the scalar to a list with only one element.
6. The correct method to leave the array empty @ Nums = ();
7. Print "there are", scalar @ Nums, "numbers! /N "; scalar is not a function. It only tells Perl to process Nums by scalar.
8. <stdin> for the input list, use Ctrl + D to end // Of course, it is in UNIX
9. Chomp is the same for the list... chomp (@ Nums); // return the number of linefeeds removed. It seems a bit useful at last.