I planned to recommend that skjeiu use the Command switch (-i~) in his solution to While loop not printing anything after using grep. My test case did not work as expected. The input file was correctly renamed as the backup. A new file was created with the original name. However, the print function sent its output to the screen rather than the file. What am I missing?

#!perl -i.bak
my @input =  <>;
if (!scalar grep {/Friday/} @input) {
    splice @input, 1, 0, "Friday\n";
}
print @input;
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using Strawberry perl on windows 7

perl -v
This is perl 5, version 30, subversion 2 (v5.30.2) built for MSWin32-x
+64-multi-t
hread
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