nl_tokens: Detects the value of an option at the tree node .
pl_tokens: function ( ast ) { let detected = [ ] ; ast . traverseByTypes ( [ 'block' , 'atrulers' ] , function ( node ) { // For the block node, find its last (the deepest) child var whitespaceNode = getLastWhitespaceNode ( node ) ; if ( whitespaceNode ) { detected . push ( whitespaceNode . <mask> ) ; } else { detected . push ( '' ) ; } } ) ; return detected ; }