Hierarchical data in C ++

Question

How can I process data in C ++, as in new dynamic languages, for example, arrays in PHP are pretty neat:

$arr = array(

"somedata" => "Hello, yo, me being a simple string",

"somearray" => array(6 => 5, 13 => 9, "a" => 42),

"simple_data_again" => 198792,

);

I am open to all suggestions.

Answer 1

If you know in advance that all types of values mapwill be held, use boost::variant. Or use boost::any. With the help of, boost::anyyou can subsequently add entries with any type of value to the map.

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Sample code with boost::variant:

Map creation:

typedef boost::variant<std::string, std::map<int, int>, int> MyVariantType;
std::map<std::string, MyVariantType> hash;

Adding entries:

hash["somedata"] = "Hello, yo, me being a simple string";
std::map<int, int> temp; 
temp[6] = 5; 
temp[13] = 9;
hash["somearray"] = temp;
hash["simple_data_again"] = 198792;

Getting Values:

std::string s = boost::get<std::string>(hash["somedata"]);
int i = boost::get<int>(hash["simple_data_again"]);

@Matthieu M , boost::variant. , boost::variant operator<, .

---

boost::any:

:

std::map<std::string, boost::any> hash;

:

hash["somedata"] = "Hello, yo, me being a simple string";
std::map<int, int> temp; 
temp[6] = 5; 
temp[13] = 9;
hash["somearray"] = temp;
hash["simple_data_again"] = 198792;

:

std::string s = boost::any_cast<std::string>(hash["somedata"]);
int i = boost::any_cast<int>(hash["simple_data_again"]);

, boost::any (). - , , .

---

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---

:

• std:: map - ++
• boost:: variant
• boost:: any

Answer 2

++ , , :

• std::map boost::variant boost::any .
• boost::property_tree

Answer 3

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Answer 4

"" ++, .

Answer 5

boost::variant " ", . , , :

std::map
<
 std::string,
 boost::variant
 <
  std::string,
  std::array<int, 4>,
  int
 >
> my_variant_array;

my_variant_array["somedata"] = "Hello, yo, me being a simple string";
my_variant_array["somearray"] = {
 1, 2, 3, 4
};
my_variant_array["simple_data_again"] = 198792;

You can even define a recursive change in such a structure containing another std::mapof boost::variant. Remember that this is something other than what you probably mean: boost::variant- it is a type of safe union of types with associated values. You can use it to implement a compiler for a dynamic language that allows you to create constructs according to your request. C ++ per se is not dynamic - everything must be strictly typed.