CairOpen Contracts

A set of libraries to help using Cairo on StarkNet.

Examples for use in other Cairo contracts are provided in examples.

Contents

• Installation
• Usage
• Libraries
  • String
  • Math
  • Binary
  • Hash
• Local setup

Installation

Protostar

protostar install CairOpen/cairo-contracts

Python

! Coming soon

Usage

To use the librairy in contracts then

# contracts/MyContract.cairo

%lang starknet

from cairopen.string.string import String
from cairopen.string.type import string

Libraries

String

String utilities to store and manipulation strings in Cairo. Docs

• Type String
• Codecs & Namespace StringCodec
  • Storage
    • StringCodec.read
    • StringCodec.write
    • StringCodec.write_from_char_arr
    • StringCodec.delete
  • Conversion
    • StringCodec.felt_to_string
    • StringCodec.ss_to_string
    • StringCodec.ss_arr_to_string
    • StringCodec.extract_last_char_from_ss
    • StringCodec.assert_char_encoding
  • Codec constants
    • StringCodec.CHAR_SIZE
    • StringCodec.LAST_CHAR_MASK
    • StringCodec.NUMERICAL_OFFSET
• Namespace StringUtil
  • Manipulation
    • StringUtil.concat
    • StringUtil.append_char
    • StringUtil.path_join
• Common constants
  • SHORT_STRING_MAX_LEN
  • SHORT_STRING_MAX_VALUE
  • STRING_MAX_LEN

Math

Mathematical utilities in Cairo. Docs

• Array
  • concat_arr
  • concat_felt_arr
  • invert_arr
  • invert_felt_arr
  • assert_felt_arr_unique

Binary

Binary utilities in Cairo. Docs

• Bits
  • Bits.extract
  • Bits.merge
  • Bits.rightshift
  • Bits.leftshift
  • Bits.rightrotate
  • Bits.negate

Hash

Hashing utilities in Cairo. Docs

• hash
  • sha256

Local setup

This project is built using Protostar

Makefile scripts

Tests: make test