  Considering the seq2seq architecture of TranX for natural language to code
translation, we identify four key components of importance: grammatical
constraints, lexical preprocessing, input representations, and copy mechanisms.
To study the impact of these components, we use a state-of-the-art architecture
that relies on BERT encoder and a grammar-based decoder for which a
formalization is provided. The paper highlights the importance of the lexical
substitution component in the current natural language to code systems.
