I was reading an article at What does context in context-free grammar refer to?The production zA -> xyis described as being an unrestricted production. In what way is it unrestricted?I even visited https://en.wikipedia.org/wiki/Unrestricted_grammarwhich talks about unrestricted grammar as the one that is comprised of productions which have no restriction on LHS or RHS. On this note, I assume that an unrestricted production is the one with no restriction on LHS or RHS.What restrictions are being talked about and how is the production free from such restrictions?
What is an unrestricted production?
formal grammars