# The V Programming Language
[](https://github.com/vlang/v/commits/master)
[](https://travis-ci.org/vlang/v)
https://vlang.io
Documentation: [vlang.io/docs](https://vlang.io/docs)
Changelog: [github.com/vlang/v/blob/master/CHANGELOG.md](https://github.com/vlang/v/blob/master/CHANGELOG.md)
Twitter: [twitter.com/v_language](https://twitter.com/v_language)
Discord (primary community): [discord.gg/n7c74HM](https://discord.gg/n7c74HM)
Installing V: [github.com/vlang/v#installing-v-from-source](https://github.com/vlang/v#installing-v-from-source)
## Key Features of V
- Simplicity: the language can be learned in less than an hour
- Fast compilation: ≈100k — 1.2 million loc/s
- Easy to develop: V compiles itself in less than a second
- Performance: within 3% of C
- Safety: no null, no globals, no undefined behavior, immutability by default
- C to V translation
- Hot code reloading
- Powerful UI and graphics libraries
- Easy cross compilation
- REPL
- Built-in ORM
- C and JavaScript backends
V 1.0 release is planned for December 2019. Right now V is in an alpha stage.
## Installing V from source
### Linux, macOS, Windows, *BSD, Solaris, WSL, Android, Raspbian
```bash
git clone https://github.com/vlang/v
cd v
make
```
That's it! Now you have a V executable at `[path to V repo]/v`. `[path to V repo]` can be anywhere.
V is being constantly updated. To update V, simply run
```
v up
```
### C compiler
You'll need Clang or GCC or Visual Studio. If you are doing development, you most likely already have one of those installed.
Otherwise follow these instructions:
[https://github.com/vlang/v/wiki/Installing-a-C-compiler-on-Linux-macOS](https://github.com/vlang/v/wiki/Installing-a-C-compiler-on-Linux-macOS)
[github.com/vlang/v/wiki/Installing-a-C-compiler-on-Windows](https://github.com/vlang/v/wiki/Installing-a-C-compiler-on-Windows)
### Symlinking
You can create a `/usr/local/bin/v` symlink so that V is globally available:
```
sudo ./v symlink
```
### Docker
```bash
git clone https://github.com/vlang/v
cd v
docker build -t vlang .
docker run --rm -it vlang:latest
v
```
### Testing and running the examples
Make sure V can compile itself:
```
v -o v compiler
```
```
$ v
V 0.1.x
Use Ctrl-C or `exit` to exit
>>> println('hello world')
hello world
>>>
```
```
cd examples
v hello_world.v && ./hello_world # or simply
v run hello_world.v # this builds the program and runs it right away
v word_counter.v && ./word_counter cinderella.txt
v run news_fetcher.v
v run tetris/tetris.v
```
In order to build Tetris and anything else using the graphics module, you will need to install glfw and freetype libraries.
If you plan to use the http package, you also need to install OpenSSL on non-Windows systems.
```
macOS:
brew install glfw freetype openssl
Debian/Ubuntu:
sudo apt install libglfw3 libglfw3-dev libfreetype6-dev libssl-dev
Arch/Manjaro:
sudo pacman -S glfw-x11 freetype2
Fedora:
sudo dnf install glfw glfw-devel freetype-devel
Windows:
git clone --depth=1 https://github.com/ubawurinna/freetype-windows-binaries [path to v repo]/thirdparty/freetype/
```
glfw dependency will be removed soon.
## JavaScript backend
[examples/hello_v_js.v](examples/hello_v_js.v):
```
fn main() {
for i := 0; i < 3; i++ {
println('Hello from V.js')
}
}
```
```bash
v -o hi.js examples/hello_v_js.v && node hi.js
Hello from V.js
Hello from V.js
Hello from V.js
```
## Troubleshooting:
https://github.com/vlang/v/wiki/Troubleshooting
## Contributing
Code structure:
https://github.com/vlang/v/blob/master/CONTRIBUTING.md
If you introduce a breaking change and rebuild V, you will no longer be able to use V to build itself. So it's a good idea to make a backup copy of a working compiler executable.