Section: Alex Lexical Analyser Generator (1)
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alex - the lexical analyser generator for Haskell
This manual page documents briefly the
This manual page was written for the Debian GNU/Linux distribution
because the original program does not have a manual page. Instead, it
has documentation in various other formats, including DVI, Info and
HTML; see below.
is a lexical analyser generator system for Haskell. It is similar to the
tool lex or flex for C/C++.
Input files are expected to be of the form
will produce output in
Caveat: When using
(Chalmers Haskell) the command argument structure is slightly
different. This is because the hbc run time system takes some flags
as its own (for setting things like the heap size, etc). This problem
can be circumvented by adding a single dash (`-') to your command
line. So when using a hbc generated version of Alex, the argument
[OPTION]... file [OPTION]...
The programs follow the usual GNU command line syntax, with long
options starting with two dashes (`--'). A summary of options is
included below. For a complete description, see the other
- -d, --debug
Instructs Alex to generate a lexer which will output debugging messages
as it runs.
- -g, --ghc
Instructs Alex to generate a lexer which is optimised for compiling with
GHC. The lexer will be significantly more efficient, both in terms of
the size of the compiled lexer and its runtime.
- -o FILE, --outfile=FILE
Specifies the filename in which the output is to be placed. By default,
this is the name of the input file with the
suffix replaced by
- -i [FILE], --info[=FILE]
Produces a human-readable rendition of the state machine (DFA) that
Alex derives from the lexer, in
where the input file is
The format of the info file is currently a bit basic, and not
- -v, --version
Print version information on standard output then exit successfully.
the Alex homepage
Alex Version 3.1.3
Copyright (c) 1995-2003, Chris Dornan and Simon Marlow
This manual page was written by Ian Lynagh
>, based on the happy manpage, for the Debian GNU/Linux
system (but may be used by others).
- SEE ALSO