typematching

Typematching is a technique used in statically typed programming languages to ensure that function arguments are of the correct type before function calls are made. This technique is also known as type checking or type verification.

In a type-inferred language, typematching is automatic and is performed by the compiler. The compiler infers the types of all expressions in the program and verifies that the function arguments are of the correct type before generating machine code for the function call.

In contrast, in a type-erased language, typematching is not necessary because the type information of the function arguments is not preserved at runtime. Instead, the type information is erased and replaced with a type token or descriptor that is used at runtime to dispatch to the correct overloaded function.

Typematching is an important safety feature in statically typed programming languages because it helps prevent type-related errors, such as null pointer dereferences and incorrect function invocations. However, it can also lead to increased compilation time and complexity in the implementation of the language.

Typematching can be performed using various techniques, including subtyping, SMT solvers, and constraints. Subtyping is a common approach used in many type systems, where a subtype of a given type is used to perform the type check. SMT solvers and constraints are used in more advanced type systems to perform satisfiability checks and type verification.

Typematching is an essential feature of many statically typed programming languages, including Rust, OCaml, and Haskell. It helps ensure the correctness and reliability of the program and prevents type-related errors that can lead to crashes and security vulnerabilities.