Dictionary

The Dictionary class is data structure that can store any type of data similar to a python dictionary.

This generic interface allows to deliver complex input data to the simulation code without the need to define a specific data structure. It can be used as followed (more details see this unit test.

NeoFOAM::Dictionary dict;

dict.insert("key1", 42);
dict.insert("key2", std::string("Hello"));

dict.get<int>("key1") == 42;
dict.get<std::string>("key2") == "Hello";

If the dictionary is not passed as a const reference, the values can be modified as well:

NeoFOAM::Dictionary dict;
dict.insert("key", 42);
dict["key"] = 43;

dict.get<int>("key") == 43;

Accessing a non-existent key will throw an exception std::out_of_range:

NeoFOAM::Dictionary dict;
dict["non_existent_key"]; // will throw with std::out_of_range;

To check if a key exists, the found method can be used:

NeoFOAM::Dictionary dict;
dict.insert("key", 42);
dict.found("key") == true;

Dictionary provides a method to remove a key:

NeoFOAM::Dictionary dict;
dict.insert("key", 42);
dict["key"] = 43;
dict.remove("key");

dict.found("key") == false;

The Dictionary class also provides a method to access a sub-dictionary. This is useful to group related data together:

NeoFOAM::Dictionary dict;
NeoFOAM::Dictionary subDict;
subDict.insert("key1", 42);
subDict.insert("key2", std::string("Hello"));

dict.insert("subDict", subDict);

NeoFOAM::Dictionary& sDict = dict.subDict("subDict");
sDict.get<int>("key1") == 42;
sDict.get<std::string>("key2") == "Hello";

sDict.get<int>("key1") = 100;

// check if the value is modified
NeoFOAM::Dictionary& sDict2 = dict.subDict("subDict");
sDict2.get<int>("key1") == 100;