rippled/include/xrpl/basics

Basics

Utility functions and classes.

The module xrpl/basics should contain no dependencies on other modules.

Choosing an xrpld container.

• std::vector

  • For ordered containers with most insertions or erases at the end.

• std::deque

  • For ordered containers with most insertions or erases at the start or end.

• std::list

  • For ordered containers with inserts and erases to the middle.
  • For containers with iterators stable over insert and erase.
  • Generally slower and bigger than std::vector or std::deque except for those cases.

• std::set

  • For sorted containers.

• xrpl::hash_set

  • Where inserts and contains need to be O(1).
  • For "small" sets, std::set might be faster and smaller.

• xrpl::hardened_hash_set

  • For data sets where the key could be manipulated by an attacker in an attempt to mount an algorithmic complexity attack: see http://en.wikipedia.org/wiki/Algorithmic_complexity_attack

The following container is deprecated

• std::unordered_set
• Use xrpl::hash_set instead, which uses a better hashing algorithm.
• Or use xrpl::hardened_hash_set to prevent algorithmic complexity attacks.