![LAZYBOY](meta/logo.png)
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---

An embedded domain-specific language + compiler written in Haskell for producing code to run on the Nintendo Game Boy.

Also features a library for manipulating constructs such as memory and graphics.

Currently, RGBASM is the only output target, but in the future native machine code generation is planned.

Syntax example (will be updated as more complex constructs are added):
```haskell
main :: IO ()
main = rom >>= T.putStrLn
    where rom = compileROM $ do
            smiley <- embedBytes image
            -- set scroll values
            write (Address scx) 0
            write (Address scy) 0
            -- set background palette
            setBackgroundPalette defaultPalette
            -- perform graphics operations
            onVblank $ do
                disableLCD
                memcpy (Name smiley) (Address $ 0x9010) $ fromIntegral $ length image
                memset (Address 0x9904) (0x992F - 0x9904) 0 -- clear the background tilemap
                write (Address background1) 1 -- write the background tile data
                setLCDControl $ defaultLCDControl { lcdDisplayEnable = True, lcdBackgroundEnable = True }
            -- halt indefinitely
            freeze

image :: [Word8]
image = [0x00,0x00,0x00,0x00,0x24,0x24,0x00,0x00,0x81,0x81,0x7e,0x7e,0x00,0x00,0x00,0x00]
```

See `app/Main.hs` for a full usage example.

Build a ROM (output will be named `main.gb`):
```
stack run > examples/main.asm
cd examples && make NAME=main
```

# About issues
I mostly use the issue tracker on here as a place to write about planned features and compiler development, 
don't take the count as an indicator of active bugs, and be sure to filter to show only issues that are bugs if you are curious on the state of the project.

# Contributing
Please see the [Contributing](https://github.com/ix/lazyboy/wiki/Contributing) page on the Wiki.

Additional information about the project can also be found on the Wiki.

# Special thanks
Thanks to [Francesco149](https://github.com/Francesco149) and [Bonzi](https://github.com/bnzis) for kindly devoting their time and knowledge to the project. The graphics functionality in particular would not be where it is without their assistance.