[C++17] Remove inheritance from std::binary_function, std::unary_function.

[ginac.git] / ginac / ex.h

diff --git a/ginac/ex.h b/ginac/ex.h
index 21df43059c645e886c7870c1078afaf70b6106e3..3b980aabafff98f9ae6bfe20c9b50b28ded03607 100644 (file)
--- a/ginac/ex.h
+++ b/ginac/ex.h
@@ -673,19 +673,19 @@ inline bool are_ex_trivially_equal(const ex &e1, const ex &e2)
 }
 
 /* Function objects for STL sort() etc. */
-struct ex_is_less : public std::binary_function<ex, ex, bool> {
+struct ex_is_less {
        bool operator() (const ex &lh, const ex &rh) const { return lh.compare(rh) < 0; }
 };
 
-struct ex_is_equal : public std::binary_function<ex, ex, bool> {
+struct ex_is_equal {
        bool operator() (const ex &lh, const ex &rh) const { return lh.is_equal(rh); }
 };
 
-struct op0_is_equal : public std::binary_function<ex, ex, bool> {
+struct op0_is_equal {
        bool operator() (const ex &lh, const ex &rh) const { return lh.op(0).is_equal(rh.op(0)); }
 };
 
-struct ex_swap : public std::binary_function<ex, ex, void> {
+struct ex_swap {
        void operator() (ex &lh, ex &rh) const { lh.swap(rh); }
 };