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Niels 2015-06-28 19:32:09 +02:00
parent 7d9cfb1b32
commit 48c4f4d05d
6 changed files with 117 additions and 10 deletions
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18
doc/examples/count.cpp Normal file
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@ -0,0 +1,18 @@
#include <json.hpp>
using namespace nlohmann;
int main()
{
// create a JSON object
json j_object = {{"one", 1}, {"two", 2}};
// call find
auto count_two = j_object.count("two");
auto count_three = j_object.count("three");
// print values
std::cout << std::boolalpha;
std::cout << "number of elements with key \"two\": " << count_two << '\n';
std::cout << "number of elements with key \"three\": " << count_three << '\n';
}

2
doc/examples/count.output Normal file
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@ -0,0 +1,2 @@
number of elements with key "two": 1
number of elements with key "three": 0

19
doc/examples/find__key_type.cpp Normal file
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@ -0,0 +1,19 @@
#include <json.hpp>
using namespace nlohmann;
int main()
{
// create a JSON object
json j_object = {{"one", 1}, {"two", 2}};
// call find
auto it_two = j_object.find("two");
auto it_three = j_object.find("three");
// print values
std::cout << std::boolalpha;
std::cout << "\"two\" was found: " << (it_two != j_object.end()) << '\n';
std::cout << "value at key \"two\": " << *it_two << '\n';
std::cout << "\"three\" was found: " << (it_three != j_object.end()) << '\n';
}

3
doc/examples/find__key_type.output Normal file
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@ -0,0 +1,3 @@
"two" was found: true
value at key "two": 2
"three" was found: false

38
src/json.hpp
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@ -2701,7 +2701,21 @@ class basic_json
m_value.array->erase(m_value.array->begin() + static_cast<difference_type>(idx));
}
/// find an element in an object
/*!
@brief find an element in a JSON object
Finds an element in a JSON object with key equivalent to @a key. If the
element is not found or the JSON value is not an object, end() is returned.
@param[in] key key value of the element to search for
@return Iterator to an element with key equivalent to @a key. If no such
element is found, past-the-end (see end()) iterator is returned.
@complexity Logarithmic in the size of the JSON object.
@liveexample{The example shows how find is used.,find__key_type}
*/
iterator find(typename object_t::key_type key)
{
auto result = end();
@ -2714,7 +2728,10 @@ class basic_json
return result;
}
/// find an element in an object
/*!
@brief find an element in a JSON object
@copydoc find(typename object_t::key_type)
*/
const_iterator find(typename object_t::key_type key) const
{
auto result = cend();
@ -2727,7 +2744,22 @@ class basic_json
return result;
}
/// returns the number of occurrences of a key in an object
/*!
@brief returns the number of occurrences of a key in a JSON object
Returns the number of elements with key @a key. If ObjectType is the
default `std::map` type, the return value will always be `0` (@a key was
not found) or `1` (@a key was found).
@param[in] key key value of the element to count
@return Number of elements with key @a key. If the JSON value is not an
object, the return value will be `0`.
@complexity Logarithmic in the size of the JSON object.
@liveexample{The example shows how count is used.,count}
*/
size_type count(typename object_t::key_type key) const
{
// return 0 for all nonobject types

47
src/json.hpp.re2c
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@ -2701,7 +2701,21 @@ class basic_json
m_value.array->erase(m_value.array->begin() + static_cast<difference_type>(idx));
}
/// find an element in an object
/*!
@brief find an element in a JSON object
Finds an element in a JSON object with key equivalent to @a key. If the
element is not found or the JSON value is not an object, end() is returned.
@param[in] key key value of the element to search for
@return Iterator to an element with key equivalent to @a key. If no such
element is found, past-the-end (see end()) iterator is returned.
@complexity Logarithmic in the size of the JSON object.
@liveexample{The example shows how find is used.,find__key_type}
*/
iterator find(typename object_t::key_type key)
{
auto result = end();
@ -2714,7 +2728,10 @@ class basic_json
return result;
}
/// find an element in an object
/*!
@brief find an element in a JSON object
@copydoc find(typename object_t::key_type)
*/
const_iterator find(typename object_t::key_type key) const
{
auto result = cend();
@ -2727,7 +2744,22 @@ class basic_json
return result;
}
/// returns the number of occurrences of a key in an object
/*!
@brief returns the number of occurrences of a key in a JSON object
Returns the number of elements with key @a key. If ObjectType is the
default `std::map` type, the return value will always be `0` (@a key was
not found) or `1` (@a key was found).
@param[in] key key value of the element to count
@return Number of elements with key @a key. If the JSON value is not an
object, the return value will be `0`.
@complexity Logarithmic in the size of the JSON object.
@liveexample{The example shows how count is used.,count}
*/
size_type count(typename object_t::key_type key) const
{
// return 0 for all nonobject types
@ -5600,15 +5632,16 @@ class basic_json
{
public:
/// constructor for strings
parser(const string_t& s, parser_callback_t cb = nullptr) : callback(cb), m_lexer(s)
parser(const string_t& s, parser_callback_t cb = nullptr)
: callback(cb), m_lexer(s)
{
// read first token
get_token();
}
/// a parser reading from an input stream
parser(std::istream& _is, parser_callback_t cb = nullptr) : callback(cb),
m_lexer(&_is)
parser(std::istream& _is, parser_callback_t cb = nullptr)
: callback(cb), m_lexer(&_is)
{
// read first token
get_token();
@ -5875,7 +5908,7 @@ class basic_json
}
private:
/// levels of recursion
/// current level of recursion
int depth = 0;
/// callback function
parser_callback_t callback;