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This commit is contained in:
Ruben Perez
2022-08-08 17:04:50 +02:00
parent 780b0d19e4
commit 50cd20bb7d
73 changed files with 1087 additions and 1219 deletions
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18
example/value.cpp
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@@ -5,7 +5,7 @@
// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
//
#include <boost/mysql/value.hpp>
#include <boost/mysql/field_view.hpp>
#include <iostream>
#define ASSERT(expr) \
@@ -18,14 +18,14 @@
void example_get()
{
//[value_example_get
boost::mysql::value v ("hello"); // v contains type boost::string_view
boost::mysql::field_view v ("hello"); // v contains type boost::string_view
boost::string_view typed_val = v.get<boost::string_view>(); // retrieves the underlying string
ASSERT(typed_val == "hello");
try
{
v.get<double>(); // wrong type! throws boost::mysql::bad_value_access
}
catch (const boost::mysql::bad_value_access&)
catch (const boost::mysql::bad_field_access&)
{
}
//]
@@ -34,7 +34,7 @@ void example_get()
void example_get_optional()
{
//[value_example_get_optional
boost::mysql::value v (3.14); // v contains type double
boost::mysql::field_view v (3.14); // v contains type double
boost::optional<double> typed_val = v.get_optional<double>();
ASSERT(typed_val.has_value()); // the optional is not empty
ASSERT(*typed_val == 3.14); // and contains the right value
@@ -49,7 +49,7 @@ void example_get_optional()
void example_get_std_optional()
{
//[value_example_get_std_optional
boost::mysql::value v (3.14); // v contains type double
boost::mysql::field_view v (3.14); // v contains type double
std::optional<double> typed_val = v.get_std_optional<double>();
ASSERT(typed_val.has_value()); // the optional is not empty
ASSERT(*typed_val == 3.14); // and contains the right value
@@ -64,7 +64,7 @@ void example_get_std_optional()
void example_get_conversions()
{
//[value_example_get_conversions
boost::mysql::value v (std::uint64_t(42)); // v contains type std::uint64_t
boost::mysql::field_view v (std::uint64_t(42)); // v contains type std::uint64_t
ASSERT(v.get<std::uint64_t>() == 42u); // exact type match
ASSERT(v.get<std::int64_t>() == 42); // converts from std::uint64_t -> std::int64_t
//]
@@ -74,7 +74,7 @@ void example_inefficient()
{
//[value_example_inefficient
// WARNING!! Inefficient, do NOT do
boost::mysql::value v (3.14); // get the value e.g. using query
boost::mysql::field_view v (3.14); // get the value e.g. using query
if (v.is_convertible_to<double>()) // it should be double, but we are not use
{
double val = v.get<double>();
@@ -91,7 +91,7 @@ void example_inefficient()
void example_inefficient_ok()
{
//[value_example_inefficient_ok
boost::mysql::value v (3.14); // get the value e.g. using query
boost::mysql::field_view v (3.14); // get the value e.g. using query
boost::optional<double> val = v.get_optional<double>();
// it should be double, but we are not use
if (val)
@@ -109,7 +109,7 @@ void example_inefficient_ok()
void example_is()
{
//[value_example_is
boost::mysql::value v (std::uint64_t(42)); // v contains type std::uint64_t
boost::mysql::field_view v (std::uint64_t(42)); // v contains type std::uint64_t
ASSERT(v.is<std::uint64_t>()); // exact type match
ASSERT(!v.is<std::int64_t>()); // does not consider conversions
ASSERT(v.is_convertible_to<std::uint64_t>()); // exact type match