Question

What is lexical scoping in R?

Answer 1

Under lexical scoping rules, if an “unknown” variable is referred to in a function, the idea is to use the version that is “in scope” in the enclosing piece of code (and apply this rule recursively) — this is the scoping rule used by R (as R is built on top of a Scheme interpreter, a LISP derivative which emphasises lexical scope). Variable bindings can be all resolved, checked and verified at compile-time – this is safer, and in many other ways better.