I know both arrays and structs count as variables, but do their fields/elements?
I’m trying to write some documentation about a program that deals with deeply nested structs and arrays, but don’t know if I can refer to these fields/elements as variables.
In ordinary documentation, words like “variable” take their meaning from context. Other options would be “value” or “datum”/”data”. As long as your explanation of your interface is clear and consistent, it probably doesn’t matter which of those you use.
(Language in Standards, and discussion of Standards, is something else. In that case, more precision and lots of definitions are required.)