{
  package foo;

  sub func1 { print "old\n" }
  sub func2 { print "older\n" }
  sub func3 { print "new\n" }

  use deprecated qw/ func1 func2 /;
}

print "calling: func1\n";
foo->func1;
print "calling: func2\n";
foo->func2;
print "calling: func3\n";
foo->func3;

print "calling: func1 again ...\n";
foo->func1;

__output__

calling: func1
deprecated subroutine 'foo::func1' at deprecated_test.pl line 13
old
calling: func2
deprecated subroutine 'foo::func2' at deprecated_test.pl line 15
older
calling: func3
new
calling: func1 again ...
old