Non-local variable

This article needs additional citations for verification. Please help improve this article by adding citations to reliable sources. Unsourced material may be challenged and removed. Find sources: "Non-local variable" – news · newspapers · books · scholar · JSTOR (January 2025) (Learn how and when to remove this message)

In programming language theory, a non-local variable is a variable that is not defined in the local scope. While the term can refer to global variables, it is primarily used in the context of nested and anonymous functions where some variables can be in neither the local nor the global scope.

In Lua they are called the upvalues of the function.^[1]