https://github.com/codex-storage/nim-contract-abi

Contract ABI Encoding
https://github.com/codex-storage/nim-contract-abi

Last synced: 2 months ago
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Contract ABI Encoding

• Host: GitHub
• URL: https://github.com/codex-storage/nim-contract-abi
• Owner: codex-storage
• License: other
• Created: 2021-11-25T08:34:37.000Z (about 3 years ago)
• Default Branch: main
• Last Pushed: 2024-02-06T08:00:23.000Z (12 months ago)
• Last Synced: 2024-07-29T00:47:00.807Z (6 months ago)
• Language: Nim
• Size: 42 KB
• Stars: 3
• Watchers: 10
• Forks: 3
• Open Issues: 0
• Metadata Files:
  • Readme: Readme.md
  • License: License.md

Awesome Lists containing this project

• awesome-nim - contract-abi - Implements encoding of parameters according to the Ethereum Contract ABI specification. (Algorithms / Blockchain)

README

        
Contract ABI

============

Implements encoding of parameters according to the Ethereum

[Contract ABI Specification][1].

Installation

------------

Use the [Nimble][2] package manager to add `contractabi` to an existing project.

Add the following to its .nimble file:

```nim

requires "contractabi >= 0.6.0 & < 0.7.0"

```

Usage

-----

```nim

import contractabi

# encode unsigned integers, booleans, enums

AbiEncoder.encode(42'u8)

# encode uint256

import stint

AbiEncoder.encode(42.u256)

# encode byte arrays and sequences

AbiEncoder.encode([1'u8, 2'u8, 3'u8])

AbiEncoder.encode(@[1'u8, 2'u8, 3'u8])

# encode tuples

AbiEncoder.encode( (42'u8, @[1'u8, 2'u8, 3'u8], true) )

# decode values of different types

AbiDecoder.decode(bytes, uint8)

AbiDecoder.decode(bytes, UInt256)

AbiDecoder.decode(bytes, array[3, uint8])

AbiDecoder.decode(bytes, seq[uint8])

# decode tuples

AbiDecoder.decode(bytes, (uint32, bool, seq[byte]) )

# add support for encoding of custom types

import questionable/results

type CustomType = object

  a: uint16

  b: string

func encode(encoder: var AbiEncoder, custom: CustomType) =

  encoder.write( (custom.a, custom.b) )

func decode(decoder: var AbiDecoder, T: type CustomType): ?!T =

  let (a, b) = ?decoder.read( (uint16, string) )

  success CustomType(a: a, b: b)

```

[1]: https://docs.soliditylang.org/en/latest/abi-spec.html

[2]: https://github.com/nim-lang/nimble