init.pp

# Install pear via package, and install necessary modules.
class manage_pear {
  include
    'pear',
    'manage_pear::packages'
  package { 'php5-dev' :
    ensure => present,
  }
}


class manage_pear::packages {
  pear::package { 'pecl/mongo':
    version => '1.2.12',
  }
}

class manage_pear::restart_apache {
  service { 'restartapache':
    name       => 'apache2',
    hasstatus  => yes,
    hasrestart => yes,
    ensure     => running,
    subscribe  => Class[manage_pear::packages],
  }
}

Class['manage_pear'] -> Class ['manage_pear::packages']