C++ concepts: BasicLockable
From cppreference.com
                    
                                        
                    
                    
                                                            
                    The BasicLockable concept describes the minimal characteristics of types that provide exclusive blocking semantics for execution agents (i.e. threads).
[edit] Requirements
For type L to be BasicLockable, the following conditions have to be satisfied for an object m of type L:
| Expression | Requires | Effects | 
|---|---|---|
| m.lock() | Blocks until a lock can be obtained for the current execution agent. If an exception is thrown, no lock is obtained. | |
| m.unlock() | The current execution agent should hold the lock m. | Releases the lock held by the execution agent. Throws no exceptions. |