Fix unarchiving empty containers.

[ginac.git] / ginac / pseries.cpp

diff --git a/ginac/pseries.cpp b/ginac/pseries.cpp
index 4dba512951ca60c36c66a51e78e98e2bd311d256..b064a202c567033511410a4479ccbccd5aeeeba3 100644 (file)
--- a/ginac/pseries.cpp
+++ b/ginac/pseries.cpp
@@ -119,17 +119,15 @@ pseries::pseries(const ex &rel_, epvector &&ops_)
 void pseries::read_archive(const archive_node &n, lst &sym_lst) 
 {
        inherited::read_archive(n, sym_lst);
-       auto first = n.find_first("coeff");
-       auto last = n.find_last("power");
-       ++last;
-       seq.reserve((last-first)/2);
+       auto range = n.find_property_range("coeff", "power");
+       seq.reserve((range.end-range.begin)/2);
 
-       for (auto loc = first; loc < last;) {
+       for (auto loc = range.begin; loc < range.end;) {
                ex rest;
                ex coeff;
                n.find_ex_by_loc(loc++, rest, sym_lst);
                n.find_ex_by_loc(loc++, coeff, sym_lst);
-               seq.push_back(expair(rest, coeff));
+               seq.emplace_back(expair(rest, coeff));
        }
 
        n.find_ex("var", var, sym_lst);