.TH FENNEL 1

.SH NAME
fennel \- a lisp programming language that runs on Lua
.SH SYNOPSIS
.B fennel
[\fB--repl\fR] |
[\fB--compile \fIfilename\fR] |
[\fB--eval \fIsource\fR] |
[\fIfilename\fP] [\fIargs ...\fR]

.SH DESCRIPTION
This manual page documents briefly the
.B fennel
command.
.PP
.B fennel
is the main entry point for Fennel, a lisp programming language that
runs on Lua runtimes. With no options or arguments, it runs an
interactive Read-Eval-Print loop (REPL).
.PP
Given a filename as its first argument, it runs that file and passes
it the subsequent arguments. Ahead-of-time compilation can be invoked
with the
.B --compile
flag, while short snippets can be evaluated with the
.B --eval
argument.

.SH OPTIONS
A summary of options is included below.
.TP
.B \-\-repl
Start an interactive repl session. This is the default when given no arguments.
.TP
.B \-\-compile \fIfilename\fP
Perform ahead-of-time compilation on the provided file and write the
Lua output to standard out.
.TP
.B \-\-eval \fIsource\fP
Evaluate a given piece of source code and print the result.
.TP
.B \-\-no-searcher
When running a repl or a file,
.B fennel.searcher
is installed by default so that the
.B require
function can load Fennel files in addition to Lua files. This flag
disables that behavior. Has no effect for ahead-of-time compilation.
.TP
.B \-\-add-package-path \fIpath\fP
Add the given path to
.B package.path
so that the
.B require
function will know to look there when searching for Lua modules.
.TP
.B \-\-add-fennel-path \fIpath\fP
Same as above, but for Fennel's path used when searching for Fennel
modules.
.TP
.B \-\-globals \fIVAR1[,VAR2...]\fP
Allow VAR1, VAR2, etc as globals in addition to the standard set of
globals. This enables strict global checking even in ahead-of-time
compilation where it otherwise would be disabled. Use "*" to disable
globals checking.
.TP
.B \-\-globals-only \fIVAR1[,VAR2...]\fP
Same as above, but without the inclusion of the standard set of globals.
.TP
.B \-\-require-as-include
Instead of loading required modules at runtime, compile them inline
into the main file being compiled. Only useful during ahead-of-time
compilation.
.TP
.B \-\-to-be-closed
When compiling
.B with-open
use the to-be-closed feature of Lua 5.4+ to avoid interfering with traces.
.TP
.B \-\-assert-as-repl
Calls to the built-in function
.B assert
from Fennel will be replaced with calls to
.B assert-repl
so that when the assertion fails, a REPL will be started in which you
can interactively debug.
.TP
.B \-\-lambda-as-fn
Replace
.B lambda
function definitions with
.B fn\fR,
removing the runtime overhead from arity checking.
.TP
.B \-\-use-bit-lib
Compile bitwise operations to use LuaJIT's bitop library instead of Lua
5.3+ bitwise operators.
.TP
.B \-\-load \fIFILE\fP
Load the specified file before any command is run.
.TP
.B \-\-compile-binary \fIFILE\fP \fIOUT\fP \fILUA_LIB\fP \fILUA_DIR\fP
Compile FILE to a standalone binary OUT using LUA_LIB and the Lua
header files in LUA_DIR. See
.B \-\-compile-binary \-\-help
for details.
.TP
.B \-\-no\-compiler\-sandbox
Do not limit compiler environment (used in macros) to minimal sandbox.
.TP
.B \-\-keywords \fIKEYWORD1[,KEYWORD2...]\fP
Treat these symbols as reserved Lua keywords.
.TP
.B \-h, \-\-help
Print a help message and exit
.TP
.B \-v, \-\-version
Print the version number and exit
.PP
Use the NO_COLOR environment variable to disable escape codes in error messages.

.SH SEE ALSO

.MR fennel-api 3 ,
.MR fennel-reference 5 ,
.MR fennel-tutorial 7

The semantics are very close to Lua, so Lua's reference manual is also helpful.

.SH COMMUNITY

The mailing list is at https://lists.sr.ht/~technomancy/fennel while
the issue tracker is at https://dev.fennel-lang.org. Most
discussion happens on the #fennel channel of Libera chat.

.SH AUTHORS
Calvin Rose and Phil Hagelberg and contributors:
https://github.com/bakpakin/Fennel/graphs/contributors

.SH LICENSE
Copyright © 2016-2025, Released under the MIT/X11 license