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Re: Print contents of text file line by lineby AnomalousMonk (Archbishop) |
on Jun 23, 2018 at 20:23 UTC ( [id://1217303]=note: print w/replies, xml ) | Need Help?? |
Further to stevieb's remarks++ about properly understanding the context in which the $fh filehandle is read in the OPed while-loop, note that if you had enabled strict at the start of your code, the code would not even have compiled due to the absence of an explicit declaration of a @line array before using it. ($line[n] accesses the @line array). So (all code examples untested) would have failed to compile and would have thrown an error message about the undeclared @line array that might have pointed you in the right debugging direction.
If a @line array had, for some reason, been declared before the while-loop, there would have been no compile-time error, but the use of the warnings module would have produced a run-time warning (not The warning will have a source code line number associated with it which should aid in understanding the nature of the problem. Bottom line: If you're a novice Perl programmer, always enable warnings and strict. If you're not a novice Perl programmer, then always enable warnings and strict — unless you have a very good and clearly understood reason not to do so. Update: As hippo pointed out, we have Tutorials in the Monastery, and Use strict and warnings is a good one about strict (and warnings). See also the supplementary links at the end of the article. Give a man a fish: <%-{-{-{-<
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