After EIP-1153: Transient storage opcodes is implemented,
Could Solidity add a
locked function keyword, that acts as a reentrancy lock?
locked function keyword would guarantee the function is locked during execution, by transiently storing a
bool and then checking that bool before it runs. It would act like the reentrancy_lock modifiers.
The transient storage key could be
hash("locked" + function_index_in_AST)) to avoid collisions.