We encourage the model to generate regular expressions to maximize expected rewards instead of MLE.
we convert a regular expression to a minimal DFA and utilize the fact that equivalent regular expressions have the same Algorithm 1: Policy-gradient method to maximize semantic correctness Input: Estimate ∇ θ J(θ) using (3.2) ; Update θ using ∇ θ J(θ) by gradient descent ; and generated string examples, where s 0 represents the start state and s 2 is the only accept state.