nl_tokens: Checks whether a property name is a writeable attribute .
pl_tokens: function shouldSetAttribute ( name , value ) { if ( isReservedProp ( name ) ) { return false ; } if ( name . <mask> > 2 && ( name [ 0 ] === 'o' || name [ 0 ] === 'O' ) && ( name [ 1 ] === 'n' || name [ 1 ] === 'N' ) ) { return false ; } if ( value === null ) { return true ; } switch ( typeof value ) { case 'boolean' : return shouldAttributeAcceptBooleanValue ( name ) ; case 'undefined' : case 'number' : case 'string' : case 'object' : return true ; default : // function, symbol return false ; } }