OCaml

OCaml is a general-purpose programming language in the ML family. It blends functional programming with imperative and object-oriented features and is the successor of Caml. It emphasizes safety, expressiveness, and performance, and is used in research, teaching, and industry.

The core language supports a strong static type system with type inference, which often eliminates explicit type annotations. It offers algebraic data types, pattern matching, and a rich module system with first-class modules and functors. Values are immutable by default, with mutable state available when declared, and objects alongside a lightweight object system provide optional object-oriented programming.

OCaml compiles to bytecode or native code, via the OCaml runtime or native code compiler. The two main compilers are ocamlc for bytecode and ocamlopt for native code. The runtime includes garbage collection, and the compiler emphasizes tail-call optimization and efficient performance. The language also offers an interactive top-level to experiment with expressions.

The OCaml ecosystem includes the OPAM package manager and the dune build system, contributing to a robust workflow for managing libraries and projects. The standard library provides a broad set of modules, and the language interoperates with C and other languages through foreign function interfaces.

OCaml has a mature user base in academia and industry. It is used in formal methods, compilers, and finance, and in large-scale software projects. Notable adopters include Jane Street and other organizations that value strong typing and robust tooling.