mirror of
https://github.com/janet-lang/janet
synced 2024-12-26 08:20:27 +00:00
236 lines
8.9 KiB
Markdown
236 lines
8.9 KiB
Markdown
[](https://gitter.im/janet-language/community)
|
|
|
|
[](https://ci.appveyor.com/project/bakpakin/janet/branch/master)
|
|
[](https://travis-ci.org/janet-lang/janet)
|
|
[](https://builds.sr.ht/~bakpakin/janet/freebsd.yml?)
|
|
[](https://builds.sr.ht/~bakpakin/janet/openbsd.yml?)
|
|
|
|
<img src="https://raw.githubusercontent.com/janet-lang/janet/master/assets/janet-w200.png" alt="Janet logo" width=200 align="left">
|
|
|
|
**Janet** is a functional and imperative programming language and bytecode interpreter. It is a
|
|
modern lisp, but lists are replaced
|
|
by other data structures (arrays, tables (hash table), struct (immutable hash table), tuples).
|
|
The language also supports bridging to native code written in C, meta-programming with macros, and bytecode assembly.
|
|
|
|
There is a repl for trying out the language, as well as the ability
|
|
to run script files. This client program is separate from the core runtime, so
|
|
Janet can be embedded into other programs. Try Janet in your browser at
|
|
[https://janet-lang.org](https://janet-lang.org).
|
|
|
|
<br>
|
|
|
|
## Use Cases
|
|
|
|
Janet makes a good system scripting language, or a language to embed in other programs.
|
|
It's like Lua and Guile in that regard. It has more built-in functionality and a richer core language than
|
|
Lua, but smaller than GNU Guile or Python.
|
|
|
|
## Features
|
|
|
|
* Minimal setup - one binary and you are good to go!
|
|
* First class closures
|
|
* Garbage collection
|
|
* First class green threads (continuations)
|
|
* Python style generators (implemented as a plain macro)
|
|
* Mutable and immutable arrays (array/tuple)
|
|
* Mutable and immutable hashtables (table/struct)
|
|
* Mutable and immutable strings (buffer/string)
|
|
* Lisp Macros
|
|
* Byte code interpreter with an assembly interface, as well as bytecode verification
|
|
* Tailcall Optimization
|
|
* Direct interop with C via abstract types and C functions
|
|
* Dynamically load C libraries
|
|
* Functional and imperative standard library
|
|
* Lexical scoping
|
|
* Imperative programming as well as functional
|
|
* REPL
|
|
* Parsing Expression Grammars built in to the core library
|
|
* 400+ functions and macros in the core library
|
|
* Embedding Janet in other programs
|
|
* Interactive environment with detailed stack traces
|
|
|
|
## Documentation
|
|
|
|
* For a quick tutorial, see [the introduction](https://janet-lang.org/docs/index.html) for more details.
|
|
* For the full API for all functions in the core library, see [the core API doc](https://janet-lang.org/api/index.html)
|
|
|
|
Documentation is also available locally in the repl.
|
|
Use the `(doc symbol-name)` macro to get API
|
|
documentation for symbols in the core library. For example,
|
|
```
|
|
(doc doc)
|
|
```
|
|
Shows documentation for the doc macro.
|
|
|
|
To get a list of all bindings in the default
|
|
environment, use the `(all-bindings)` function. You
|
|
can also use the `(doc)` macro with no arguments if you are in the repl
|
|
to show bound symbols.
|
|
|
|
## Source
|
|
|
|
You can get the source on [GitHub](https://github.com/janet-lang/janet) or
|
|
[SourceHut](https://git.sr.ht/~bakpakin/janet). While the GitHub repo is the official repo,
|
|
the SourceHut mirror is actively maintained.
|
|
|
|
## Building
|
|
|
|
### macos and Unix-like
|
|
|
|
The Makefile is non-portable and requires GNU-flavored make.
|
|
|
|
```
|
|
cd somewhere/my/projects/janet
|
|
make
|
|
make test
|
|
make repl
|
|
```
|
|
|
|
### 32-bit Haiku
|
|
|
|
32-bit Haiku build instructions are the same as the unix-like build instructions,
|
|
but you need to specify an alternative compiler, such as `gcc-x86`.
|
|
|
|
```
|
|
cd somewhere/my/projects/janet
|
|
make CC=gcc-x86
|
|
make test
|
|
make repl
|
|
```
|
|
|
|
### FreeBSD
|
|
|
|
FreeBSD build instructions are the same as the unix-like build instuctions,
|
|
but you need `gmake` to compile. Alternatively, install directly from
|
|
packages, using `pkg install lang/janet`.
|
|
|
|
```
|
|
cd somewhere/my/projects/janet
|
|
gmake
|
|
gmake test
|
|
gmake repl
|
|
```
|
|
|
|
### Windows
|
|
|
|
1. Install [Visual Studio](https://visualstudio.microsoft.com/thank-you-downloading-visual-studio/?sku=Community&rel=15#) or [Visual Studio Build Tools](https://visualstudio.microsoft.com/thank-you-downloading-visual-studio/?sku=BuildTools&rel=15#)
|
|
2. Run a Visual Studio Command Prompt (cl.exe and link.exe need to be on the PATH) and cd to the directory with janet.
|
|
3. Run `build_win` to compile janet.
|
|
4. Run `build_win test` to make sure everything is working.
|
|
|
|
### Meson
|
|
|
|
Janet also has a build file for [Meson](https://mesonbuild.com/), a cross platform build
|
|
system. Although Meson has a python dependency, Meson is a very complete build system that
|
|
is maybe more convenient and flexible for integrating into existing pipelines.
|
|
Meson also provides much better IDE integration than Make or batch files, as well as support
|
|
for cross compilation.
|
|
|
|
For the impatient, building with Meson is as follows. The options provided to
|
|
`meson setup` below emulate Janet's Makefile.
|
|
|
|
```sh
|
|
git clone https://github.com/janet-lang/janet.git
|
|
cd janet
|
|
meson setup build \
|
|
--buildtype release \
|
|
--optimization 2 \
|
|
-Dgit_hash=$(git log --pretty=format:'%h' -n 1)
|
|
ninja -C build
|
|
|
|
# Run the binary
|
|
build/janet
|
|
|
|
# Installation
|
|
ninja -C build install
|
|
```
|
|
|
|
## Development
|
|
|
|
Janet can be hacked on with pretty much any environment you like, but for IDE
|
|
lovers, [Gnome Builder](https://wiki.gnome.org/Apps/Builder) is probably the
|
|
best option, as it has excellent meson integration. It also offers code completion
|
|
for Janet's C API right out of the box, which is very useful for exploring. VSCode, Vim,
|
|
Emacs, and Atom will have syntax packages for the Janet language, though.
|
|
|
|
## Installation
|
|
|
|
See [the Introduction](https://janet-lang.org/introduction.html) for more details. If you just want
|
|
to try out the language, you don't need to install anything. You can also move the `janet` executable wherever you want on your system and run it.
|
|
|
|
## Usage
|
|
|
|
A repl is launched when the binary is invoked with no arguments. Pass the -h flag
|
|
to display the usage information. Individual scripts can be run with `./janet myscript.janet`
|
|
|
|
If you are looking to explore, you can print a list of all available macros, functions, and constants
|
|
by entering the command `(all-bindings)` into the repl.
|
|
|
|
```
|
|
$ janet
|
|
Janet 1.7.1-dev-951e10f Copyright (C) 2017-2020 Calvin Rose
|
|
janet:1:> (+ 1 2 3)
|
|
6
|
|
janet:2:> (print "Hello, World!")
|
|
Hello, World!
|
|
nil
|
|
janet:3:> (os/exit)
|
|
$ janet -h
|
|
usage: build/janet [options] script args...
|
|
Options are:
|
|
-h : Show this help
|
|
-v : Print the version string
|
|
-s : Use raw stdin instead of getline like functionality
|
|
-e code : Execute a string of janet
|
|
-r : Enter the repl after running all scripts
|
|
-p : Keep on executing if there is a top level error (persistent)
|
|
-q : Hide prompt, logo, and repl output (quiet)
|
|
-k : Compile scripts but do not execute (flycheck)
|
|
-m syspath : Set system path for loading global modules
|
|
-c source output : Compile janet source code into an image
|
|
-n : Disable ANSI color output in the repl
|
|
-l path : Execute code in a file before running the main script
|
|
-- : Stop handling options
|
|
```
|
|
|
|
If installed, you can also run `man janet` and `man jpm` to get usage information.
|
|
|
|
## Embedding
|
|
|
|
Janet can be embedded in a host program very easily. The normal build
|
|
will create a file `build/janet.c`, which is a single C file
|
|
that contains all the source to Janet. This file, along with
|
|
`src/include/janet.h` and `src/include/janetconf.h` can dragged into any C
|
|
project and compiled into the project. Janet should be compiled with `-std=c99`
|
|
on most compilers, and will need to be linked to the math library, `-lm`, and
|
|
the dynamic linker, `-ldl`, if one wants to be able to load dynamic modules. If
|
|
there is no need for dynamic modules, add the define
|
|
`-DJANET_NO_DYNAMIC_MODULES` to the compiler options.
|
|
|
|
See the [Embedding Section](https://janet-lang.org/capi/embedding.html) on the website for more information.
|
|
|
|
## Examples
|
|
|
|
See the examples directory for some example janet code.
|
|
|
|
## Discussion
|
|
|
|
Feel free to ask questions and join discussion on the [Janet Gitter Channel](https://gitter.im/janet-language/community).
|
|
Alternatively, check out [the #janet channel on Freenode](https://webchat.freenode.net/)
|
|
|
|
## FAQ
|
|
|
|
### Why is my terminal is spitting out junk when I run the repl?
|
|
|
|
Make sure your terminal supports ANSI escape codes. Most modern terminals will
|
|
support these, but some older terminals, windows consoles, or embedded terminals
|
|
will not. If your terminal does not support ANSI escape codes, run the repl with
|
|
the `-n` flag, which disables color output. You can also try the `-s` if further issues
|
|
ensue.
|
|
|
|
## Why Janet
|
|
|
|
Janet is named after the almost omniscient and friendly artificial being in [The Good Place](https://en.wikipedia.org/wiki/The_Good_Place).
|
|
|
|
<img src="https://raw.githubusercontent.com/janet-lang/janet/master/assets/janet-the-good-place.gif" alt="Janet logo" width="115px" align="left">
|