Rope fixes

arBmind · arBmind · commit 2e124dd9034a · 2020-07-19T19:21:31.000+02:00
* empty Rope can now be be stored
* ropeAppend now declares no return type
diff --git a/src/string19.lib/string19/Rope.Decimal.h b/src/string19.lib/string19/Rope.Decimal.h
@@ -16,7 +16,7 @@ template<size_t N> constexpr auto ropeCount(ADL*, Decimal<N>*) -> size_t {
     return c;
 }
 
-template<size_t N> constexpr auto ropeAppend(ADL*, char*& data, Decimal<N>*) {
+template<size_t N> constexpr void ropeAppend(ADL*, char*& data, Decimal<N>*) {
     auto c = ropeCount(adl, decimal<N>);
     auto n = N;
     for (int o = c - 1; o >= 0; o--, n /= 10) data[o] = n % 10 + '0';
diff --git a/src/string19.lib/string19/Rope.Rope.h b/src/string19.lib/string19/Rope.Rope.h
@@ -4,14 +4,16 @@
 
 namespace string19 {
 
-template<class... Ts> constexpr auto ropeAppend(ADL*, char*& data, const Rope<Ts...>& rope) {
-    rope.parts.visitAll([&](const auto& p) { ropeAppend(adl, data, p); });
-}
-
 template<class... Ts> constexpr auto ropeCount(ADL*, const Rope<Ts...>& rope) -> size_t {
     auto result = size_t{};
     rope.parts.visitAll([&](const auto& p) { result += ropeCount(adl, p); });
     return result;
 }
+template<> constexpr auto ropeCount(ADL*, const Rope<>&) -> size_t { return {}; }
+
+template<class... Ts> constexpr void ropeAppend(ADL*, char*& data, const Rope<Ts...>& rope) {
+    rope.parts.visitAll([&](const auto& p) { ropeAppend(adl, data, p); });
+}
+template<> constexpr void ropeAppend(ADL*, char*&, const Rope<>&) {}
 
 } // namespace string19
diff --git a/src/string19.lib/string19/Rope.StringStore.h b/src/string19.lib/string19/Rope.StringStore.h
@@ -6,7 +6,7 @@ namespace string19 {
 
 template<size_t N> constexpr auto ropeCount(ADL*, const StringStore<N>&) -> size_t { return N; }
 
-template<size_t N> constexpr auto ropeAppend(ADL*, char*& data, const StringStore<N>& s) {
+template<size_t N> constexpr void ropeAppend(ADL*, char*& data, const StringStore<N>& s) {
     for (auto i = 0u; i < N; ++i) *data++ = s[i];
 }
 
diff --git a/src/string19.lib/string19/Rope.StringView.h b/src/string19.lib/string19/Rope.StringView.h
@@ -6,7 +6,7 @@ namespace string19 {
 
 constexpr auto ropeCount(ADL*, StringView sv) -> size_t { return sv.count; }
 
-constexpr auto ropeAppend(ADL*, char*& data, StringView sv) {
+constexpr void ropeAppend(ADL*, char*& data, StringView sv) {
     for (auto i = 0u; i < sv.count; ++i) *data++ = sv[i];
 }
 
diff --git a/src/string19.lib/string19/Rope.char.h b/src/string19.lib/string19/Rope.char.h
@@ -5,6 +5,6 @@ namespace string19 {
 
 constexpr auto ropeCount(ADL*, char) -> size_t { return 1; }
 
-constexpr auto ropeAppend(ADL*, char*& data, char c) { *data++ = c; }
+constexpr void ropeAppend(ADL*, char*& data, char c) { *data++ = c; }
 
 } // namespace string19
diff --git a/src/string19.lib/string19/Rope.join.test.cpp b/src/string19.lib/string19/Rope.join.test.cpp
@@ -11,6 +11,14 @@
 
 using namespace string19;
 
+TEST(Rope, joinEmpty) {
+    constexpr auto rope = Seperator{','}.join();
+    constexpr auto N = ropeCount(rope);
+    constexpr auto store = ropeStore<N>(rope);
+    static_assert(viewStore(store) == viewLiteral(""));
+    EXPECT_EQ(store, storeLiteral(""));
+}
+
 TEST(Rope, joinChar) {
     constexpr auto rope = Seperator{','}.join('1', '2', '3');
     constexpr auto N = ropeCount(rope);
@@ -20,7 +28,7 @@ TEST(Rope, joinChar) {
 }
 
 TEST(Rope, joinView) {
-    constexpr auto rope = Seperator{viewLiteral(", ")}.join('1', '2', '3');
+    constexpr auto rope = Seperator{viewLiteral(", ")}.join(viewLiteral("1"), '2', '3');
     constexpr auto N = ropeCount(rope);
     constexpr auto store = ropeStore<N>(rope);
     static_assert(viewStore(store) == viewLiteral("1, 2, 3"));

Original file line number	Diff line number	Diff line change
`@@ -16,7 +16,7 @@ template<size_t N> constexpr auto ropeCount(ADL, Decimal<N>) -> size_t {`
`16`	`16`	`return c;`
`17`	`17`	`}`
`18`	`18`
`19`		`-template<size_t N> constexpr auto ropeAppend(ADL, char& data, Decimal<N>*) {`
	`19`	`+template<size_t N> constexpr void ropeAppend(ADL, char& data, Decimal<N>*) {`
`20`	`20`	`auto c = ropeCount(adl, decimal<N>);`
`21`	`21`	`auto n = N;`
`22`	`22`	`for (int o = c - 1; o >= 0; o--, n /= 10) data[o] = n % 10 + '0';`
Original file line number	Diff line number	Diff line change
`@@ -6,7 +6,7 @@ namespace string19 {`
`6`	`6`
`7`	`7`	`template<size_t N> constexpr auto ropeCount(ADL*, const StringStore<N>&) -> size_t { return N; }`
`8`	`8`
`9`		`-template<size_t N> constexpr auto ropeAppend(ADL, char& data, const StringStore<N>& s) {`
	`9`	`+template<size_t N> constexpr void ropeAppend(ADL, char& data, const StringStore<N>& s) {`
`10`	`10`	`for (auto i = 0u; i < N; ++i) *data++ = s[i];`
`11`	`11`	`}`
`12`	`12`
Original file line number	Diff line number	Diff line change
`@@ -6,7 +6,7 @@ namespace string19 {`
`6`	`6`
`7`	`7`	`constexpr auto ropeCount(ADL*, StringView sv) -> size_t { return sv.count; }`
`8`	`8`
`9`		`-constexpr auto ropeAppend(ADL, char& data, StringView sv) {`
	`9`	`+constexpr void ropeAppend(ADL, char& data, StringView sv) {`
`10`	`10`	`for (auto i = 0u; i < sv.count; ++i) *data++ = sv[i];`
`11`	`11`	`}`
`12`	`12`