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Try it Live

Run AccessList examples in the interactive playground
New to access lists? Start with Fundamentals for guided examples and gas cost analysis.

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Type Definition

Array of items where each item specifies a contract address and storage keys to pre-warm for gas savings. 
export type AccessList = readonly Item[];

export type Item = {
  address: AddressType;              // 20-byte contract address
  storageKeys: readonly HashType[];  // 32-byte storage slot keys
};

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API Methods

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Constructors

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Type Guards

  • is - Check if value is AccessList
  • isItem - Check if value is Item
  • assertValid - Validate structure

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Queries

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Manipulation

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Gas Analysis

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Conversions

  • toBytes - Convert to RLP bytes for transaction encoding

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Usage Example

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Effect Schema

import { AccessListSchema } from '@tevm/voltaire/AccessList/effect'

const addr = new Uint8Array(20)
const slot = new Uint8Array(32)
const list = AccessListSchema.create().withAddress(addr).withStorageKey(addr, slot)
list.hasSavings()

import { AccessList, Address, Hash } from 'tevm';

// Create addresses and storage keys
const token = Address('0xA0b86991c6cC137282C01B19e27F0f0751D85f469e');
const balanceSlot = Hash('0x0000000000000000000000000000000000000000000000000000000000000003');

// Build access list
let list = AccessList.create();
list = list.withAddress(token);
list = list.withStorageKey(token, balanceSlot);

// Analyze gas costs
const cost = list.gasCost();
const savings = list.gasSavings();

console.log(`Cost: ${cost} gas`);       // 4,300
console.log(`Savings: ${savings} gas`); // 100

// Check if beneficial (savings > cost)
if (list.hasSavings()) {
  transaction.accessList = list;
}

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Optimization

AccessList provides efficient APIs for gas analysis and manipulation.

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Specification