nl_tokens: 7 . 2 Testing and Comparison Operations https : // tc39 . github . io / ecma262 / #sec - testing - and - comparison - operations 7 . 2 . 2 IsArray ( argument ) https : // tc39 . github . io / ecma262 / #sec - isarray
pl_tokens: function IsArray ( argument ) { return Array . isArray ? <mask> . isArray ( argument ) : argument instanceof Object ? argument instanceof Array : Object . prototype . toString . call ( argument ) === "[object Array]" ; }