Name resolution (programming languages)

In programming languages, name resolution is the resolution of the tokens within program expressions to the intended program components. Expressions in computer programs reference variables, data types, functions, classes, objects, libraries, packages and other entities by name. In that context, name resolution refers to the association of those not-necessarily-unique names with the intended program entities. The algorithms that determine what those identifiers refer to in specific contexts are part of the language definition. The complexity of these algorithms is influenced by the sophistication of the language. For example, name resolution in assembly language usually involves only a single simple table lookup, while name resolution in C++ is extremely complicated as it involves: namespaces, which make it possible for an identifier to have different meanings depending on its associated namespace; scopes, which make it possible for an identifier to have different meanings at different scope levels, and which involves various scope overriding and hiding rules. At the most basic level name resolution usually attempts to find the binding in the smallest enclosing scope, so that for example local variables supersede global variables; this is called shadowing. visibility rules, which determine whether identifiers from specific namespaces or scopes are visible from the current context; overloading, which makes it possible for an identifier to have different meanings depending on how it is used, even in a single namespace or scope; accessibility, which determines whether identifiers from an otherwise visible scope are actually accessible and participate in the name resolution process. In programming languages, name resolution can be performed either at compile time or at runtime. The former is called static name resolution, the latter is called dynamic name resolution. A somewhat common misconception is that dynamic typing implies dynamic name resolution. For example, Erlang is dynamically typed but has static name resolution.