As big-step operational semantics is about evaluating an expression to a final value, can we state that for defining a concurrent language one needs small-step semantics, as concurrent programs need not result in a value?
1 Answer
Coinductive Big-Step Semantics for Concurrency by Tarmo Uustalu writes:
Second, contrary to what is so often stated, concurrency is not inherently small-step, or at least not more inherently than any kind of effect produced incrementally during a program’s run (e.g., interactive output). Big-step semantics for concurrency can be built by borrowing the suitable denotational machinery, except that we do not want to use domains and fixpoints to deal with partiality, but coinductively defined sets and corecursion.
So the answer is that it is stated throughout the literature, but it is not true.