pointerlevel

Pointerlevel is a concept used in type systems to describe the depth of indirection of a value. It measures how many pointer dereferences are needed to reach the underlying non-pointer type. Formally, for a type T, if T is a pointer to U, then pointerlevel(T) = 1 + pointerlevel(U); base types have level 0. In languages such as C and C++, this corresponds to the number of asterisks in a type declaration. For example, int has pointerlevel 0, int* has pointerlevel 1, and int** has pointerlevel 2.

The concept helps communicate how much indirection a value carries, which is relevant for understanding dereferencing, memory access, and potential aliasing. It also appears in discussions of templates, generics, or type inference, where the level of indirection can influence how functions accept parameters or return values, and how safety or ownership semantics are enforced.

Notes on qualifiers and syntax: qualifiers like const can apply to the pointer or to the pointed-to type, depending on the language syntax. For example, in many C-family languages, const int* and int const* both have pointerlevel 1, even though constness affects what is pointed to. Deeply nested pointers (high pointerlevel) are often associated with increased complexity and potential safety concerns, and some style guides discourage excessive indirection.

Limitations: pointerlevel is not a formal language construct in all languages; it is primarily a descriptive notion used in documentation, teaching, and tooling. Some languages use references, smart pointers, or other abstractions that change how indirection is expressed, making pointerlevel less directly applicable. Examples: int a; // level 0, int* p; // level 1, int** pp; // level 2.