export interface LayoutGridSpans { [ keys ] : number ; } export interface LayoutParameters { columnCount : number ; columnSpans : LayoutGridSpans ; rowSpans : LayoutGridSpans ; } export abstract class LayoutConfiguration < PARAM = LayoutParameters > { public xl : PARAM ; public lg : PARAM ; public md : PARAM ; public sm : PARAM ; public xs : PARAM ; constructor ( ) { this . init ( ) ; } abstract init ( ) ; }