Standard ML of New Jersey User’s Guide

SML/NJ is free and open source software, governed by a BSD 3 Clause License. For links to downloadable installers for macOS and Windows, see the README for the most recent release at Index of versions. To build the current (legacy) release from source, see the README file for the legacy repository.

A FAQ for SML/NJ is "under suspended development" and is thus still very fragmentary and incomplete.

How to get started with sml: how to compile and run programs.

The SML/NJ compilation manager, CM, organizes and optimizes the compilation process. CM calculates and caches the dependence graph between modules. When a module has been edited and is recompiled, CM compares the export type-signature of the new module to that of the old, to minimize the number of modules that need to be recompiled. See the CM Manual for details.

An (incomplete and outdated) explanation of the error messages printed by the SML/NJ compiler.

A set of structures, including SMLofNJ and its substructures, provides special system functionality for SML programs. Included with this group are the structures Cont and Susp that introduce first-class continuations and suspensions, respectively.

SML/NJ supports some extensions to the Standard ML language, such as record expressions and patterns, OR patterns, and higher-order functors.

This structure contains user-settable flags to control the operation of the compiler and interactive system, and also interfaces to individual phases of the SML/NJ compiler.

The Standard ML '97 language is almost, but not quite, compatible with the 1990 definition supported by earlier versions of SML/NJ. In the very unlikely event that one needs to convert code predating the introduction of Standard ML '97, this conversion guide explains the differences, and gives examples of how to convert SML \'90 code to be SML \'97 code.

This library consists of the types, functions, and interfaces that are part of the ML standard, including modules for I/O, the operating-system interface, arithmetic on integers, reals, and words (unsigned integers), mathematical functions, operations on strings and substrings, and so on.

The SML/NJ Library contains library and utility functions that are not part of the standard Standard. The SML/NJ library includes modules for binary search trees, adjustable arrays, and other useful data structures in the Util directory. The Unix directory supplies additional Unix-specific features, while the HTML directory supports processing web pages.

A lexical-analyzer generator similar to the classic Unix lex.

A parser generator similar to the classic Unix yacc, but with syntax error repair features.