Yul+
A low-level, highly efficient extension to Yul, an intermediate smart-contract language for the Ethereum Virtual Machine.
Features
- All existing Yul features
- Memory structures (
mstruct
) - Enums (
enum
) - Constants (
const
) - Ethereum standard ABI signature/topic generation (
sig"function ..."
,topic"event ...
) - Booleans (
true
,false
) - Safe math (over/under flow protection for addition, subtraction, multiplication)
- Injected methods (
mslice
andrequire
)
Coming Soon
- Static typing
- CLI support
Install
npm install -g yulp
Library Usage
const yulp = ;const source = yulp; console;
Enums
Here we have a fully featured enum
identifier which acts as a constant.
object "contract" code enum // logs 2 as a topic
Constants
const
will define a let
variable value that cannot be re-assigned.
object "contract" code const firstVar := 0xaa const someOther := 1
Memory Slice
mslice(position, length)
will return a 1-32 byte value from memory.
object "contract" code // will log 0xaaaa
Booleans
true
and false
are added and equate to values 0x01
and 0x00
.
object "contract" code // will log 0x01
Multi mstore sugar
mstore
can now be used as a proxy method
object "contract" code /* mstore(30, 1) mstore(add(30, 32), 2) mstore(add(30, 64), 3) mstore(add(30, 96), 4) */
Comparison Methods
lte
, gte
, neq
can now be used.
if and(lte(1, 10), gte(5, 2)) {
let k := neq(0, 1)
}
MAX_UINT
MAX_UINT
literal is now available (i.e. uint(-1)
)
if lt(v, MAX_UINT) {
let k := 1
}
Ethereum Standard ABI Signature and Topic Generation
sig" [ method abi ] "
will equate to a 4 byte method signature hex value
topic" [ event abi definition ] "
will equate to the 32 byte topic hash
object "contract" code const storeSig := sig"function store(uint256 val)" const eventSig := topic"event Store (uint256 indexed val)" // will log 0x6057361d // will log 0xddf252ad1be2c89b69c2b068fc378daa952ba7f163c4a11628f55a4df523b3ef
Memory Structures
Memory structures enable better handling of pre-existing in-memory structures.
mstruct Identifier ( [ property, ... ] )
A structure property is defined by an identifier and length specifier (i.e. blockProducer:32
) where the identifier is blockProducer
and the length is 32 bytes
.
In-memory array like structures are defined using a name.length
property, followed by a name:[array item size]
property.
Note, mstruct
properties allow for data chunk sizes up to 32 bytes only.
Inheritance
object "Utils" code const Size := 1 -> {} object "SimpleStore" is "Utils" code
Imports
We now support basic file system usage, we don't support local path resolution just yet.
The fs
object is simply supplied at compile
: yulp.compile(source, fs)
.
object "SimpleStore" is "Utils" ...
Error Reporting
A new experimental (post v0.0.7) feature is the error"some message"
literal.
This simply utf8 encodes the message to bytes, keccak256 hashes it and returns the first 4 bytes as an error identifier.
The compiler will return an errors
property ({ [4 byte idenfitier]: [error message], ... }
).
object "contract" code // example structure in memory of a BlockHeader starting at mem. position 400 // block producer // previous block hash // block height // length of anotherArray (i.e. 3 array items) // array with 3 elements, 0xaaaa, 0xbbbb, 0xcccc // Ethereum block number // transaction roots array length // transaction roots, one 4 byte item 0xffffffff mstruct BlockHeader // will return 0xaa BlockHeaderblockProducersize // will return 32 BlockHeader // will return block height 0xcc BlockHeaderblockHeight // will return pos + length BlockHeaderblockHeight // will return pos BlockHeaderblockHeightsize // 32 BlockHeaderblockHeightindex // 2 BlockHeaderblockHeight // keccak256 hash the block height BlockHeader // will return anotherArray item 0xcccc BlockHeadersize400 // will return the size of the entire struct BlockHeader // will return entire offset position of the struct pos + length BlockHeader // keccak256 hash the entire block header
Help out
There is always a lot of work to do, and will have many rules to maintain. So please help out in any way that you can:
- Create, enhance, and debug fuel-core rules (see our guide to "Working on rules").
- Improve documentation.
- Chime in on any open issue or pull request.
- Open new issues about your ideas for making
yulp
better, and pull requests to show us how your idea works. - Add new tests to absolutely anything.
- Create or contribute to ecosystem tools.
- Spread the word!
We communicate via issues and pull requests.
Important documents
Donate
Please consider donating if you think Yul+ is helpful to you or that my work is valuable. We are happy if you can help us buy a cup of coffee. ❤️
Or just send us some Dai, USDC or Ether:
0x3e947a271a37Ae7B59921c57be0a3246Ee0d887C Etherscan
Coming Soon
mstruct mstruct mstruct