nl_tokens: Returns true if the specified value is a stream
pl_tokens: function isStream ( obj ) { return Boolean ( obj && isFunction ( obj . addListener ) && isFunction ( obj . removeListener ) && isFunction ( obj . <mask> ) && ( isFunction ( obj . write ) && isFunction ( obj . end ) || isFunction ( obj . pipe ) && isFunction ( obj . read ) && isFunction ( obj . pause ) && isFunction ( obj . resume ) ) ) ; }