Remove fp::operator-

include/fmt/format-inl.h

@@ -452,12 +452,6 @@ class fp {
 
 inline bool operator==(fp x, fp y) { return x.f == y.f && x.e == y.e; }
 
-// Returns an fp number representing x - y. Result may not be normalized.
-inline fp operator-(fp x, fp y) {
-  FMT_ASSERT(x.f >= y.f && x.e == y.e, "invalid operands");
-  return {x.f - y.f, x.e};
-}
-
 inline uint64_t multiply(uint64_t lhs, uint64_t rhs) {
 #if FMT_USE_INT128
   auto product = static_cast<__uint128_t>(lhs) * rhs;

test/format-impl-test.cc

@@ -250,12 +250,6 @@ TEST(FPTest, ComputeFloatBoundaries) {
   }
 }
 
-TEST(FPTest, Subtract) {
-  auto v = fp(123, 1) - fp(102, 1);
-  EXPECT_EQ(v.f, 21u);
-  EXPECT_EQ(v.e, 1);
-}
-
 TEST(FPTest, Multiply) {
   auto v = fp(123ULL << 32, 4) * fp(56ULL << 32, 7);
   EXPECT_EQ(v.f, 123u * 56u);