---
name: "ml-ulex"
section: "1"
platform: "linux"
package: "smlnj"
version: "110.99.9-1"
release: "Arch Linux 2026-11-01"
platforms: ["linux"]
url: "https://new.carta.tech/ml-ulex"
---

# ml-ulex(1)

a Unicode-compatible lexical analyser generator for Standard ML

## NAME

ml-ulex - a Unicode-compatible lexical analyser generator for Standard ML

## SYNOPSIS

**ml-ulex** \[*OPTIONS*\] *file*

## DESCRIPTION

**ML-Ulex** is a lexer generator that supports Unicode characters (in UTF-8 representation) and an extended form of regular expressions.

## OPTIONS

- **-32**

  run the 32-bit version of the program (currently the default).

- **-64**

  run the 64-bit version of the program.  This option only applies to the **x86-64** (aka **amd64**) architecture.

- **--dot**

  generate DOT output ( \<http://www.graphviz.org\>). The generated file will be named `file.dot`, where `file` is the input file.

- **--match**

  enter interactive matching mode.  This will allow interactive testing of the machine; presently, only the `INITIAL` start state is available for testing (see the *User Guide* \<http://www.smlnj.org/doc/ml-lpt/manual.pdf\> for details on start states).

- **--ml-lex-mode**

  operate in **ml-lex** compatibility mode.

- **--table-based**

  generate a table-based lexer.

- **--fn-based**

  generate a lexer that represents states as functions and transitions as tail calls.

- **--minimize**

  generate a minimal machine.  Note that this is slow, and is almost never necessary.

- **--strict-sml**

  generate strict SML (*i.e.*, do not use SML/NJ extensions).  This flag is useful if you want to use the output with a different SML system.

## AUTHOR

**ML-Ulex** was written by Aaron Turon.

## SEE-ALSO

[ml-antlr(1)](/ml-antlr/1.md), [ml-yacc(1)](/ml-yacc/1.md)

The *SML/NJ Language Processing Tools: User Guide \<https://www.smlnj.org/doc/ml-lpt/manual.pdf\>.*

**Regular-expression derivatives reexamined** *by Scott Owens, John Reppy, and Aaron Turon.* *Journal of Functional Programming, 19(2):173-190, 2009.*

## COPYING

*Copyright © 2020 The Fellowship of SML/NJ*

*This is free software; see the source for copying  conditions.   There  is  NO* *warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.*