By default, the  . (dot) regex metacharacter matches everything except a newline. Use the  /s modifier to make dot match everything. 

c:\@Work\Perl\monks>perl -wMstrict -le
"use Data::Dump qw(pp);
 ;;
 for my $s (qq{yz}, qq{yz\n}) {
   $s =~ m{ (.) \z }xms;
   printf qq{in %s matched %s \n}, pp($s), pp($1);
   }
"
in "yz" matched "z"
in "yz\n" matched "\n"

[download]
See also  \z for "absolute end of string" anchor.

Update: You're also running into an interaction with  $ which matches | which by default matches at "the end of the line (or before newline at the end)", so even with the  /s modifier, the first position at which  .$ can possibly match (scanning from left to right) is before a newline, if present; remember that the matching rule is leftmost longest.

Give a man a fish:  <%-{-{-{-<

In reply to Re: How to match last character of string, even if it happens to be a newline? by AnomalousMonk
in thread How to match last character of string, even if it happens to be a newline? by Allasso

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