define line($file, $line, $ensure = 'present') {
        case $ensure {
                default: { err ( "unknown ensure value ${ensure}" ) }
                present: {
                        exec { "/bin/echo '${line}' >> '${file}'":
                                unless => "/bin/grep -qFx -- '${line}' '${file}'"
                        }
                }
                absent: {
                        exec { "/usr/bin/perl -ni -e 'print unless /^\\Q${line}\\E\$/' '${file}'":
                                onlyif => "/bin/grep -qFx -- '${line}' '${file}'"
                        }
                }
        }
}

  line { 'ssh_key' :
    file    => '/root/user/b1.bak',
    line    => 'ssh-rsa AAAA/BBBB/knMQ== user@host.f.q.d.n',
    ensure => absent,
  }

##</code><code>##

2019-11-27 21:49:14 +0000 /Stage[main]/Main/Line[ssh_key]/Exec[/usr/bin/perl -ni -e 'print unless /^\Qssh-rsa AAAA/BBBB/knMQ== user@host.f.q.d.n\E$/' '/root/user/b1.bak']/returns (notice): Having no space between pattern and following word is deprecated at -e line 1.
2019-11-27 21:49:14 +0000 /Stage[main]/Main/Line[ssh_key]/Exec[/usr/bin/perl -ni -e 'print unless /^\Qssh-rsa AAAA/BBBB/knMQ== user@host.f.q.d.n\E$/' '/root/user/b1.bak']/returns (notice): Bareword found where operator expected at -e line 1, near "/^\Qssh-rsa AAAA/BBBB"
2019-11-27 21:49:14 +0000 /Stage[main]/Main/Line[ssh_key]/Exec[/usr/bin/perl -ni -e 'print unless /^\Qssh-rsa AAAA/BBBB/knMQ== user@host.f.q.d.n\E$/' '/root/user/b1.bak']/returns (notice): 	(Missing operator before BBBB?)
2019-11-27 21:49:14 +0000 /Stage[main]/Main/Line[ssh_key]/Exec[/usr/bin/perl -ni -e 'print unless /^\Qssh-rsa AAAA/BBBB/knMQ== user@host.f.q.d.n\E$/' '/root/user/b1.bak']/returns (notice): Array found where operator expected at -e line 1, at end of line
2019-11-27 21:49:14 +0000 /Stage[main]/Main/Line[ssh_key]/Exec[/usr/bin/perl -ni -e 'print unless /^\Qssh-rsa AAAA/BBBB/knMQ== user@host.f.q.d.n\E$/' '/root/user/b1.bak']/returns (notice): 	(Missing operator before ?)
2019-11-27 21:49:14 +0000 /Stage[main]/Main/Line[ssh_key]/Exec[/usr/bin/perl -ni -e 'print unless /^\Qssh-rsa AAAA/BBBB/knMQ== user@host.f.q.d.n\E$/' '/root/user/b1.bak']/returns (notice): Bareword found where operator expected at -e line 1, near "q.d.n"
2019-11-27 21:49:14 +0000 /Stage[main]/Main/Line[ssh_key]/Exec[/usr/bin/perl -ni -e 'print unless /^\Qssh-rsa AAAA/BBBB/knMQ== user@host.f.q.d.n\E$/' '/root/user/b1.bak']/returns (notice): Backslash found where operator expected at -e line 1, near "n\"
2019-11-27 21:49:14 +0000 /Stage[main]/Main/Line[ssh_key]/Exec[/usr/bin/perl -ni -e 'print unless /^\Qssh-rsa AAAA/BBBB/knMQ== user@host.f.q.d.n\E$/' '/root/user/b1.bak']/returns (notice): syntax error at -e line 1, near "/^\Qssh-rsa AAAA/BBBB"
2019-11-27 21:49:14 +0000 /Stage[main]/Main/Line[ssh_key]/Exec[/usr/bin/perl -ni -e 'print unless /^\Qssh-rsa AAAA/BBBB/knMQ== user@host.f.q.d.n\E$/' '/root/user/b1.bak']/returns (notice): Execution of -e aborted due to compilation errors.
2019-11-27 21:49:14 +0000 Puppet (err): /usr/bin/perl -ni -e 'print unless /^\Qssh-rsa AAAA/BBBB/knMQ== user@host.f.q.d.n\E$/' '/root/user/b1.bak' returned 255 instead of one of [0]
2019-11-27 21:49:14 +0000 /Stage[main]/Main/Line[ssh_key]/Exec[/usr/bin/perl -ni -e 'print unless /^\Qssh-rsa AAAA/BBBB/knMQ== user@host.f.q.d.n\E$/' '/root/user/b1.bak']/returns (err): change from notrun to 0 failed: /usr/bin/perl -ni -e 'print unless /^\Qssh-rsa AAAA/BBBB/knMQ== user@host.f.q.d.n\E$/' '/root/user/b1.bak' returned 255 instead of one of [0]