gh-tenequm-claude-plugins-foundry-solidity/skills/skill/references/chisel.md

Chisel REPL

Interactive Solidity REPL for quick experimentation.

Starting Chisel

# Basic REPL
chisel

# With fork
chisel --fork-url https://eth-mainnet.g.alchemy.com/v2/KEY

# Specific block
chisel --fork-url $RPC_URL --fork-block-number 18000000

Basic Usage

➜ uint256 x = 42
➜ x * 2
Type: uint256
├ Hex: 0x54
├ Hex (full word): 0x0000000000000000000000000000000000000000000000000000000000000054
└ Decimal: 84

➜ address alice = address(0x1234)
➜ alice.balance
Type: uint256
└ Decimal: 0

Commands

Command	Description
!help	Show all commands
!clear	Clear session state
!source	Show generated source
!rawstack	Show raw stack output
!edit	Open in editor
!export	Export session to script

Session Management

# List saved sessions
chisel list

# Load session
chisel load my-session

# Save current session (in REPL)
!save my-session

# Clear cache
chisel clear-cache

Working with Contracts

➜ interface IERC20 {
    function balanceOf(address) external view returns (uint256);
}

➜ IERC20 usdc = IERC20(0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48)

➜ usdc.balanceOf(0x47ac0Fb4F2D84898e4D9E7b4DaB3C24507a6D503)
Type: uint256
└ Decimal: 1234567890

Math Testing

Quick calculations without deploying:

➜ uint256 a = 1000000
➜ uint256 b = 3
➜ a / b
Type: uint256
└ Decimal: 333333

➜ (a * 1e18) / b
Type: uint256
└ Decimal: 333333333333333333333333

Hash Functions

➜ keccak256("hello")
Type: bytes32
└ 0x1c8aff950685c2ed4bc3174f3472287b56d9517b9c948127319a09a7a36deac8

➜ keccak256(abi.encode(uint256(1), address(0x1234)))

ABI Encoding

➜ abi.encode(uint256(42), address(0x1234))
➜ abi.encodePacked("hello", "world")
➜ abi.encodeWithSelector(bytes4(0x12345678), 100)

Use Cases

1. Quick math: Test calculations before implementing
2. ABI encoding: Debug encoding issues
3. Hash verification: Check keccak256 outputs
4. Contract interaction: Test calls on fork
5. Solidity syntax: Experiment with new features

Configuration

Chisel inherits project settings from foundry.toml:

[profile.default]
solc = "0.8.30"
evm_version = "prague"

Run chisel from project root to use these settings.