public Expression MaybeAddDebugInfo(Expression expr, IPersistentMap spanMap)
 {
     if (_isDebuggable && spanMap != null & _docInfo != null)
     {
         if (Compiler.GetLocations(spanMap, out int startLine, out int startCol, out int finishLine, out int finishCol))
         {
             return(AstUtils.AddDebugInfo(expr,
                                          _docInfo,
                                          new Microsoft.Scripting.SourceLocation(0, startLine, startCol),
                                          new Microsoft.Scripting.SourceLocation(0, finishLine, finishCol)));
         }
     }
     return(expr);
 }