variableuse

Variableuse, also written as variable use, is a term used in computer science and formal logic to denote an occurrence of a variable within an expression, term, or program. It is distinguished from a variable's binding or definition. In most languages, a variable use corresponds to a point where the variable's current value affects computation; the left-hand side of an assignment typically constitutes a definition, while the right-hand side contains one or more uses.

In compiler theory, tracking variable uses supports analyses such as def-use chains, data-flow analysis, and register allocation. A definition-use chain links each assignment to the places where that value may be read later, enabling optimizations and error detection. Live-variable analysis determines which uses remain needed at a program point.

In formal logic and lambda calculus, a variable use refers to an occurrence of a variable within a term, which can be free or bound depending on the surrounding abstractions. Proper handling of variable use is essential for correct substitution, alpha-conversion, and maintaining scope rules.

Variable use is also used in static analysis and software tooling to detect unused variables, aliasing, or potential runtime errors. Understanding uses alongside definitions helps programmers optimize code and reason about program semantics.