-- | Test if a given span starts and ends at the same location.
isNullSpan :: SrcSpan -> Bool
isNullSpan ss = srcSpanStartLine ss == srcSpanEndLine ss &&
                    srcSpanStartColumn ss >= srcSpanEndColumn ss
isNullSpan :: SrcSpan -> Bool
isNullSpan ss = srcSpanStartLine ss == srcSpanEndLine ss &&
                    srcSpanStartColumn ss >= srcSpanEndColumn ss
isNullSpan ss = srcSpanStartLine ss == srcSpanEndLine ss &&
                    srcSpanStartColumn ss >= srcSpanEndColumn ss