Splat

Since definitions of vertical nonterminals consist of several production rules, these rules can be distributed over the grammar and not focused in one place. This may be bad, especially if most of the rules are collected together, and only one or two are elsewhere.

Related smells: ZigZag

Reference

Mats Stijlaart and Vadim Zaytsev. 2017. Towards a taxonomy of grammar smells. In Proceedings of the 10th ACM SIGPLAN International Conference on Software Language Engineering (SLE 2017). ACM, New York, NY, USA, 43-54.