if (!Convert.ImplicitConversionExists (rc, a.Expr, source_type)) {
rc.Report.Error (1936, loc, "An implementation of `{0}' query expression pattern for source type `{1}' could not be found",
if (!Convert.ImplicitConversionExists (rc, a.Expr, source_type)) {
rc.Report.Error (1936, loc, "An implementation of `{0}' query expression pattern for source type `{1}' could not be found",