the preferred style is to use a scalar variable for a file handle: open(my $N, '<', $filename);

I will agree with this in the context of a sub that opens a file and closes it before returning, or that returns a file handle. Indeed, I would argue that using a global handle in either of those cases is incorrect. However, I will quibble with this at top-level as in this case: there is no functional difference between the lexical file handles in your example and the traditional global file handles — in both cases, a handle opened at top-level is defined until the end of the script and valid until closed.

Please correct me if I am somehow misinformed about this.

PS: Our questioner forgot error handling, so I will point out that open ... or die is an important Perl idiom that is hidden in your example behind the autodie pragma.


In reply to Re^2: Summing numbers in a file by jcb
in thread Summing numbers in a file by pvfki

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