Standard ML of New Jersey (SML/NJ; Standard Meta-Language of New Jersey) is a compiler and integrated development environment for the programming language Standard ML. It is written in Standard ML, except for the runtime system in C language. It was originally developed jointly by Bell Laboratories and Princeton University. It is free and open-source software released under a permissive software license (BSD-like). Its name is a reference both to the American state of New Jersey in which Princeton and Bell Labs are located, and to Standard Oil of New Jersey, the famous oil monopoly of the early 20th century.

Features

SML/NJ extends the SML'97 Basis Library with several added top-level structures: Also, SML/NJ provides some syntactic constructs that are not standard features of SML'97:

Development

Successor ML is a term used to describe the next version of the language. The documents describing it have been extracted from the SML/NJ '97 files and made available as a GitHub repository of TeX documents which the community is expected to collaborate and grow the language. Successor ML features can be enabled using the command-line option. Since at least 1998, MLton is the standard bootstrapping compiler, and includes some support for Successor ML. In 2008, work began on HaMLet, a reference implementation of Successor ML written entirely in Standard ML., HaMLet remains the only complete implementation of Successor ML, with added novel features. Since 2015, the evolution of SML/NJ geared towards evolving the Basis library and adding support for the Successor ML definition with the release of version 110.79. At the end of 2020, 64-bit support was added with the release of version 110.99.