Switch to C++17. (#5959)

Co-authored-by: Gereon Kremer <nafur42@gmail.com>

1 files changed, 4 insertions, 2 deletions

diff --git a/src/expr/node.h b/src/expr/node.h
index 75d4d2022..559ce5ddb 100644
--- a/src/expr/node.h
+++ b/src/expr/node.h
@@ -1451,8 +1451,10 @@ NodeTemplate<ref_count>::substitute(Iterator substitutionsBegin,
   }
 
   // otherwise compute
-  Iterator j = find_if(substitutionsBegin, substitutionsEnd,
-                       bind2nd(first_equal_to<typename Iterator::value_type::first_type, typename Iterator::value_type::second_type>(), *this));
+  Iterator j = find_if(
+      substitutionsBegin,
+      substitutionsEnd,
+      [this](const auto& subst){ return subst.first == *this; });
   if(j != substitutionsEnd) {
     Node n = (*j).second;
     cache[*this] = n;