nl_tokens: 把background 属性拆分 e . g . background : #fff url ( ... ) repeat - x 0px top ;
pl_tokens: function ( ) { var <mask> , value ; if ( ! this [ 'background' ] ) { // 有 background 属性的 style 才能拆分 background  return ; } // 撕裂 background-position if ( value = this [ 'background-position' ] ) { value = value . trim ( ) . replace ( / \s{2} / g , '' ) . split ( ' ' ) ; if ( ! value [ 1 ] ) { value [ 1 ] = value [ 0 ] ; } this [ 'background-position-x' ] = value [ 0 ] ; this [ 'background-position-y' ] = value [ 1 ] ; } background = BI . analyse ( this [ 'background' ] ) ; if ( background . length != 1 ) { // FIXME 暂时跳过多背景的属性 return ; } background = background [ 0 ] ; if ( background [ 'background-image' ] ) { // 把原来缩写的 background 属性删掉 this . removeProperty ( 'background' ) ; this . extend ( background ) ; } }