Indeed so: CRs can sneak in and ruin your day.

Looking at:  $_ =~ s/[\r\n]+\z//s ; makes me twitch a bit, since the values of "\r" and "\n" can vary. However, the best known case of  "\n" ne "\x0A" is (old) Mac systems where  "\n" eq "\x0D" and  "\r" eq "\x0A", so  [\r\n] appears safe. [Nevertheless, I haven't found anything that guarantees that "\n" and "\r" are duals. perlport touches on systems where they aren't ASCII at all, but that's a whole other world of pain.]

Anyway, I favour:  $_ =~ s/\s+\z// ; on the basis that it finesses the issue and gets rid of any other trailing whitespace -- two birds, one stone.

Mind you, I have seen "\s" defined to be [ \t\n\r\f] -- but current perlreref says it's "whitespace".

In reply to Re^4: Make my script faster and more efficient by gone2015
in thread Make my script faster and more efficient by sesemin

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