- new item storage

- formatting of numbers using to_chars

include/cif++/CifUtils.hpp

@@ -209,7 +209,7 @@ inline auto coloured(std::basic_string<CharT, Traits, Alloc> &s, StringColour fo
 // --------------------------------------------------------------------
 
 /// std::from_chars for floating point types.
-template <typename FloatType>
+template <typename FloatType, std::enable_if_t<std::is_floating_point_v<FloatType>, int> = 0>
 std::from_chars_result from_chars(const char *first, const char *last, FloatType &value)
 {
 	std::from_chars_result result{first, {}};
@@ -329,6 +329,92 @@ std::from_chars_result from_chars(const char *first, const char *last, FloatType
 	return result;
 }
 
+enum class chars_format
+{
+    scientific		= 1,
+    fixed			= 2,
+    // hex,
+    general = fixed | scientific
+};
+
+template <typename FloatType, std::enable_if_t<std::is_floating_point_v<FloatType>, int> = 0>
+std::to_chars_result to_chars(char *first, char *last, FloatType &value, chars_format fmt)
+{
+	int size = last - first;
+	int r;
+
+	switch (fmt)
+	{
+		case chars_format::scientific:
+			if constexpr (std::is_same_v<FloatType, long double>)
+				r = snprintf(first, last - first, "%le", value);
+			else
+				r = snprintf(first, last - first, "%e", value);
+			break;
+
+		case chars_format::fixed:
+			if constexpr (std::is_same_v<FloatType, long double>)
+				r = snprintf(first, last - first, "%lf", value);
+			else
+				r = snprintf(first, last - first, "%f", value);
+			break;
+
+		case chars_format::general:
+			if constexpr (std::is_same_v<FloatType, long double>)
+				r = snprintf(first, last - first, "%lg", value);
+			else
+				r = snprintf(first, last - first, "%g", value);
+			break;
+	}
+
+	std::to_chars_result result;
+	if (r < 0 or r >= size)
+		result = { first, std::errc::value_too_large };
+	else
+		result = { first + r, std::errc() };
+
+	return result;
+}
+
+template <typename FloatType, std::enable_if_t<std::is_floating_point_v<FloatType>, int> = 0>
+std::to_chars_result to_chars(char *first, char *last, FloatType &value, chars_format fmt, int precision)
+{
+	int size = last - first;
+	int r;
+
+	switch (fmt)
+	{
+		case chars_format::scientific:
+			if constexpr (std::is_same_v<FloatType, long double>)
+				r = snprintf(first, last - first, "%.*le", precision, value);
+			else
+				r = snprintf(first, last - first, "%.*e", precision, value);
+			break;
+
+		case chars_format::fixed:
+			if constexpr (std::is_same_v<FloatType, long double>)
+				r = snprintf(first, last - first, "%.*lf", precision, value);
+			else
+				r = snprintf(first, last - first, "%.*f", precision, value);
+			break;
+
+		case chars_format::general:
+			if constexpr (std::is_same_v<FloatType, long double>)
+				r = snprintf(first, last - first, "%.*lg", precision, value);
+			else
+				r = snprintf(first, last - first, "%.*g", precision, value);
+			break;
+	}
+
+	std::to_chars_result result;
+	if (r < 0 or r >= size)
+		result = { first, std::errc::value_too_large };
+	else
+		result = { first + r, std::errc() };
+
+	return result;
+}
+
 // --------------------------------------------------------------------
 //	A progress bar
 

include/cif++/v2/category.hpp

@@ -147,9 +147,19 @@ class category_t
 	{
 	}
 
-	category_t(const category_t &) = default;
+	category_t(const category_t &rhs)
+		: m_allocator(std::allocator_traits<allocator_type>::select_on_container_copy_construction(rhs.get_allocator()))
+		, m_name(rhs.m_name)
+		, m_columns(rhs.m_columns)
+	{
+		// for (value_type r : rhs)
+		// 	this->emplace(r);
+	}
+
+	category_t(category_t &&)
+	{
 
-	category_t(category_t &&) = default;
+	}
 
 	template <typename Alloc2>
 	category_t(const category_t &c, const Alloc2 &a)
@@ -165,8 +175,15 @@ class category_t
 	{
 	}
 
-	category_t &operator=(const category_t &) = default;
-	category_t &operator=(category_t &&) = default;
+	category_t &operator=(const category_t &)
+	{
+
+	}
+
+	category_t &operator=(category_t &&)
+	{
+
+	}
 
 	~category_t()
 	{
@@ -241,6 +258,16 @@ class category_t
 		return {*this, nullptr};
 	}
 
+	size_t size() const
+	{
+		return std::distance(cbegin(), cend());
+	}
+
+	bool empty() const
+	{
+		return m_head == nullptr;
+	}
+
 	// --------------------------------------------------------------------
 
 	template <typename... Ts, typename... Ns>
@@ -264,6 +291,11 @@ class category_t
 		return this->emplace(items.begin(), items.end());
 	}
 
+	iterator emplace(value_type row)
+	{
+		// return 
+	}
+
 	template <typename ItemIter>
 	iterator emplace(ItemIter b, ItemIter e)
 	{

include/cif++/v2/item.hpp

@@ -26,25 +26,26 @@
 
 #pragma once
 
-#include <cstring>
 #include <charconv>
+#include <cstring>
 #include <iomanip>
+#include <limits>
 #include <memory>
 #include <optional>
-#include <limits>
+
+#include <cif++/CifUtils.hpp>
 
 namespace cif
 {
-	extern int VERBOSE;
+extern int VERBOSE;
 }
 
-
 namespace cif::v2
 {
 
 // --------------------------------------------------------------------
 /// \brief item is a transient class that is used to pass data into rows
-
+///        but it also takes care of formatting data
 class item
 {
   public:
@@ -52,28 +53,51 @@ class item
 
 	item(std::string_view name, char value)
 		: m_name(name)
-		, m_value({ value })
+		, m_value(m_buffer, 1)
 	{
+		m_buffer[0] = value;
+		m_buffer[1] = 0;
 	}
 
 	template <typename T, std::enable_if_t<std::is_floating_point_v<T>, int> = 0>
 	item(std::string_view name, const T &value, int precision)
 		: m_name(name)
-#if defined(__cpp_lib_format)
-		, m_value(std::format(".{}f", value, precision))
-#endif
 	{
-#if not defined(__cpp_lib_format)
-		// TODO: implement
-		m_value = std::to_string(value);
-#endif
+		auto r = cif::to_chars(m_buffer, m_buffer + sizeof(m_buffer) - 1, value, cif::chars_format::fixed, precision);
+		if (r.ec != std::errc())
+			throw std::runtime_error("Could not format number");
+		
+		assert(r.ptr >= m_buffer and r.ptr < m_buffer + sizeof(m_buffer));
+		*r.ptr = 0;
+		m_value = std::string_view(m_buffer, r.ptr - m_buffer);
 	}
 
-	template <typename T, std::enable_if_t<std::is_arithmetic_v<T>, int> = 0>
+	template <typename T, std::enable_if_t<std::is_floating_point_v<T>, int> = 0>
 	item(const std::string_view name, const T &value)
 		: m_name(name)
 		, m_value(std::to_string(value))
 	{
+		auto r = cif::to_chars(m_buffer, m_buffer + sizeof(m_buffer) - 1, value, cif::chars_format::general);
+		if (r.ec != std::errc())
+			throw std::runtime_error("Could not format number");
+		
+		assert(r.ptr >= m_buffer and r.ptr < m_buffer + sizeof(m_buffer));
+		*r.ptr = 0;
+		m_value = std::string_view(m_buffer, r.ptr - m_buffer);
+	}
+
+	template <typename T, std::enable_if_t<std::is_integral_v<T>, int> = 0>
+	item(const std::string_view name, const T &value)
+		: m_name(name)
+		, m_value(std::to_string(value))
+	{
+		auto r = std::to_chars(m_buffer, m_buffer + sizeof(m_buffer) - 1, value);
+		if (r.ec != std::errc())
+			throw std::runtime_error("Could not format number");
+		
+		assert(r.ptr >= m_buffer and r.ptr < m_buffer + sizeof(m_buffer));
+		*r.ptr = 0;
+		m_value = std::string_view(m_buffer, r.ptr - m_buffer);
 	}
 
 	item(const std::string_view name, const std::string_view value)
@@ -90,8 +114,8 @@ class item
 
 	item &operator=(item &&rhs) noexcept = default;
 
-	const std::string &name() const { return m_name; }
-	const std::string &value() const { return m_value; }
+	std::string_view name() const { return m_name; }
+	std::string_view value() const { return m_value; }
 
 	void value(const std::string &v) { m_value = v; }
 
@@ -105,17 +129,18 @@ class item
 	bool is_unknown() const { return m_value == "?"; }
 
 	size_t length() const { return m_value.length(); }
-	const char *c_str() const { return m_value.c_str(); }
+	// const char *c_str() const { return m_value.c_str(); }
 
   private:
-	std::string m_name;
-	std::string m_value;
+	std::string_view m_name;
+	std::string_view m_value;
+	char m_buffer[64];		// TODO: optimize this magic number, might be too large
 };
 
 // --------------------------------------------------------------------
 // Transient object to access stored data
 
-template<typename Row>
+template <typename Row>
 struct item_handle
 {
 	using row_type = Row;
@@ -232,7 +257,6 @@ struct item_handle
 	}
 
   private:
-
 	uint16_t m_column;
 	row_type &m_row;
 	// bool mConst = false;
@@ -276,7 +300,7 @@ struct item_handle<Row>::item_value_as<T, std::enable_if_t<std::is_arithmetic_v<
 		return result;
 	}
 
-	static int compare(const item_handle &ref, const T& value, bool icase)
+	static int compare(const item_handle &ref, const T &value, bool icase)
 	{
 		int result = 0;
 
@@ -358,7 +382,7 @@ struct item_handle<Row>::item_value_as<T, std::enable_if_t<std::is_same_v<T, boo
 	{
 		bool rv = convert(ref);
 		return value && rv ? 0
-							: (rv < value ? -1 : 1);
+		                   : (rv < value ? -1 : 1);
 	}
 };
 

include/cif++/v2/row.hpp

@@ -121,28 +121,42 @@ class row_handle
 	using category_type = Category;
 	using row_type = std::conditional_t<std::is_const_v<category_type>, const typename category_type::row, typename category_type::row>;
 
+	row_handle() = default;
+	
+	row_handle(const row_handle &) = default;
+	row_handle(row_handle &&) = default;
+
+	row_handle &operator=(const row_handle &) = default;
+	row_handle &operator=(row_handle &&) = default;
+
 	row_handle(category_type &cat, row_type &row)
-		: m_cat(cat)
-		, m_row(row) {}
+		: m_cat(&cat)
+		, m_row(&row) {}
+
+
+	explicit operator bool() const
+	{
+		return m_cat != nullptr and m_row != nullptr;
+	}
 
 	item_handle<row_type> operator[](uint32_t column_ix)
 	{
-		return item_handle<row_type>(column_ix, m_row);
+		return item_handle<row_type>(column_ix, *m_row);
 	}
 
 	const item_handle<const row_type> operator[](uint32_t column_ix) const
 	{
-		return item_handle<const row_type>(column_ix, m_row);
+		return item_handle<const row_type>(column_ix, *m_row);
 	}
 
 	item_handle<row_type> operator[](std::string_view column_name)
 	{
-		return item_handle<row_type>(get_column_ix(column_name), m_row);
+		return item_handle<row_type>(get_column_ix(column_name), *m_row);
 	}
 
 	const item_handle<const row_type> operator[](std::string_view column_name) const
 	{
-		return item_handle<const row_type>(get_column_ix(column_name), m_row);
+		return item_handle<const row_type>(get_column_ix(column_name), *m_row);
 	}
 
 	template <typename... Ts, size_t N>
@@ -166,11 +180,11 @@ class row_handle
 
 	uint32_t get_column_ix(std::string_view name) const
 	{
-		return m_cat.get_column_ix(name);
+		return m_cat->get_column_ix(name);
 	}
 
-	category_type &m_cat;
-	row_type &m_row;
+	category_type *m_cat = nullptr;
+	row_type *m_row = nullptr;
 };
 
 

test/unit-v2-test.cpp

@@ -78,24 +78,24 @@ bool init_unit_test()
 
 BOOST_AUTO_TEST_CASE(cc_1)
 {
-	std::tuple<std::string_view,float,char> tests[] = {
-		{ "1.0", 1.0, 0 },
-		{ "1.0e10", 1.0e10, 0 },
-		{ "-1.1e10", -1.1e10, 0 },
-		{ "-.2e11", -.2e11, 0 },
-		{ "1.3e-10", 1.3e-10, 0 },
-
-		{ "1.0 ", 1.0, ' ' },
-		{ "1.0e10 ", 1.0e10, ' ' },
-		{ "-1.1e10 ", -1.1e10, ' ' },
-		{ "-.2e11 ", -.2e11, ' ' },
-		{ "1.3e-10 ", 1.3e-10, ' ' },
-
-		{ "3.0", 3.0, 0 },
-		{ "3.0 ", 3.0, ' ' },
-	
-		{ "3.000000", 3.0, 0 },
-		{ "3.000000 ", 3.0, ' ' },
+	std::tuple<std::string_view, float, char> tests[] = {
+		{"1.0", 1.0, 0},
+		{"1.0e10", 1.0e10, 0},
+		{"-1.1e10", -1.1e10, 0},
+		{"-.2e11", -.2e11, 0},
+		{"1.3e-10", 1.3e-10, 0},
+
+		{"1.0 ", 1.0, ' '},
+		{"1.0e10 ", 1.0e10, ' '},
+		{"-1.1e10 ", -1.1e10, ' '},
+		{"-.2e11 ", -.2e11, ' '},
+		{"1.3e-10 ", 1.3e-10, ' '},
+
+		{"3.0", 3.0, 0},
+		{"3.0 ", 3.0, ' '},
+
+		{"3.000000", 3.0, 0},
+		{"3.000000 ", 3.0, ' '},
 	};
 
 	for (const auto &[txt, val, ch] : tests)
@@ -108,24 +108,42 @@ BOOST_AUTO_TEST_CASE(cc_1)
 		if (ch != 0)
 			BOOST_CHECK_EQUAL(*ptr, ch);
 	}
+}
+
+BOOST_AUTO_TEST_CASE(cc_2)
+{
+	std::tuple<float, int, std::string_view> tests[] = {
+		{ 1.1, 1, "1.1" }
+	};
+
+	for (const auto &[val, prec, test] : tests)
+	{
+		char buffer[64];
+		const auto &[ptr, ec] = cif::to_chars(buffer, buffer + sizeof(buffer), val, cif::chars_format::fixed, prec);
 
+		BOOST_CHECK(ec == std::errc());
+
+		BOOST_CHECK_EQUAL(buffer, test);
+	}
 }
 
+
+
 // --------------------------------------------------------------------
 
 BOOST_AUTO_TEST_CASE(r_1)
 {
 	cif::v2::category c("foo");
 	c.emplace({
-		{ "f-1", 1 },
-		{ "f-2", "two" },
-		{ "f-3", 3.0 },
+		{"f-1", 1},
+		{"f-2", "two"},
+		{"f-3", 3.0, 3},
 	});
 
 	auto row = c.front();
 	BOOST_CHECK_EQUAL(row["f-1"].compare(1), 0);
 	BOOST_CHECK_EQUAL(row["f-2"].compare("two"), 0);
-	BOOST_CHECK_EQUAL(row["f-3"].compare(3.0), 0);	// This fails when running in valgrind... sigh
+	BOOST_CHECK_EQUAL(row["f-3"].compare(3.0), 0); // This fails when running in valgrind... sigh
 }
 
 BOOST_AUTO_TEST_CASE(r_2)
@@ -134,25 +152,22 @@ BOOST_AUTO_TEST_CASE(r_2)
 
 	for (size_t i = 1; i < 256; ++i)
 	{
-		c.emplace({
-			{ "id", i },
-			{ "txt", std::string(i, 'x') }
-		});
+		c.emplace({{"id", i},
+			{"txt", std::string(i, 'x')}});
 	}
-
 }
 
 BOOST_AUTO_TEST_CASE(c_1)
 {
 	cif::v2::category c("foo");
 
-	c.emplace({ { "id", 1 }, { "s", "aap" } });
-	c.emplace({ { "id", 2 }, { "s", "noot" } });
-	c.emplace({ { "id", 3 }, { "s", "mies" } });
+	c.emplace({{"id", 1}, {"s", "aap"}});
+	c.emplace({{"id", 2}, {"s", "noot"}});
+	c.emplace({{"id", 3}, {"s", "mies"}});
 
 	int n = 1;
 
-	const char *ts[] = { "aap", "noot", "mies" };
+	const char *ts[] = {"aap", "noot", "mies"};
 
 	for (auto r : c)
 	{
@@ -177,7 +192,7 @@ BOOST_AUTO_TEST_CASE(c_1)
 
 	n = 1;
 
-	for (const auto &[i, s] : c.rows<int,std::string>("id", "s"))
+	for (const auto &[i, s] : c.rows<int, std::string>("id", "s"))
 	{
 		BOOST_CHECK_EQUAL(i, n);
 		BOOST_CHECK_EQUAL(s.compare(ts[n - 1]), 0);
@@ -185,16 +200,29 @@ BOOST_AUTO_TEST_CASE(c_1)
 	}
 }
 
-
 BOOST_AUTO_TEST_CASE(c_2)
 {
+	std::tuple<int,const char*> D[] = {
+		{1, "aap"},
+		{2, "noot"},
+		{3, "mies"}
+	};
+
 	cif::v2::category c("foo");
 
-	c.emplace({ { "id", 1 }, { "s", "aap" } });
-	c.emplace({ { "id", 2 }, { "s", "noot" } });
-	c.emplace({ { "id", 3 }, { "s", "mies" } });
+	for (const auto &[id, s] : D)
+		c.emplace({ {"id", id}, { "s", s} });
+
+	BOOST_CHECK(not c.empty());
+	BOOST_CHECK_EQUAL(c.size(), 3);
 
-	
+	cif::v2::category c2(c);
+
+	for (auto r : c)
+		c2.emplace(r);
+
+	BOOST_CHECK(not c2.empty());
+	BOOST_CHECK_EQUAL(c2.size(), 3);
 
 }
 
@@ -306,7 +334,6 @@ BOOST_AUTO_TEST_CASE(c_2)
 // 	auto &test = db["test"];
 // 	BOOST_CHECK(test.size() == 5);
 
-
 // 	BOOST_CHECK(test.exists("value"_key == cif::null));
 // 	BOOST_CHECK(test.find("value"_key == cif::null).size() == 2);
 // }
@@ -2045,4 +2072,3 @@ BOOST_AUTO_TEST_CASE(c_2)
 // 		BOOST_CHECK_EQUAL(text, kS[i++].s);
 // 	}
 // }
-