Memoization Considerations for ModuleBase

[ryanmrichard]

Right now whether a module can be memoized or not is handled by the Module class. The module developer ultimately knows whether memoization of a module is even possible. There needs to be a mechanism for module developers to signal whether or not their module is memoizable. This issue proposes a similar API to that of the Module class namely:

• add bool m_is_memoizable_ to ModuleBase (defaults to true)
• add public method bool is_memoizable() const noexcept to ModuleBase
• add protected method void turn_on_memoization() noexcept to ModuleBase
• add protected method void turn_off_memoization() noexcept to ModuleBase
• Have ModuleBase::is_memoizable() == false always make Module::is_memoizable() return false