Compilation failure

[ostronom]

[ostronom@ostronom-vaio less]$ lessc plusstrap.less
ParseError: Unrecognised input in /home/ostronom/ThirdParty/plusstrap/less/mixins.less on line 532, column 46:
531 width: ((@gridColumnWidth) * @columnSpan) + (@gridGutterWidth * (@columnSpan - 1)) - 16; // 16 is total padding on left and right of table cells
532 margin-left: 0; // undo default grid column styles
533 }