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# Ethereum Compatibility
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Ethereum address handling and compatibility utilities for cross-chain functionality and EVM integration.
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## Capabilities
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### Ethereum Address Encoding
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Convert public keys and addresses to Ethereum format.
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```typescript { .api }
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/**
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 * Encode address or public key to Ethereum format
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 * @param addressOrPublic - SS58 address or public key bytes
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 * @returns Ethereum address (0x prefixed, 40 hex chars)
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 */
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function ethereumEncode(addressOrPublic: string | Uint8Array): string;
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/**
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 * Check if string is valid Ethereum address
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 * @param address - Address string to check
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 * @returns true if valid Ethereum address format
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 */
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function isEthereumAddress(address: string): boolean;
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/**
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 * Check Ethereum address checksum validity
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 * @param address - Ethereum address to validate
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 * @returns true if checksum is valid
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 */
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function isEthereumChecksum(address: string): boolean;
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```
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### Address Conversion
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Convert between SS58 and EVM address formats.
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```typescript { .api }
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/**
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 * Convert SS58 address to EVM format
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 * @param address - SS58 address string
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 * @returns 20-byte EVM address
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 */
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function addressToEvm(address: string): Uint8Array;
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/**
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 * Convert EVM address to SS58 format
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 * @param evmAddress - 20-byte EVM address
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 * @param prefix - SS58 network prefix
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 * @param hashType - Hash algorithm ('blake2' or 'keccak')
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 * @returns SS58 address string
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 */
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function evmToAddress(evmAddress: Uint8Array, prefix?: number, hashType?: 'blake2' | 'keccak'): string;
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```
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**Usage Examples:**
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```typescript
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import { 
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  ethereumEncode,
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  isEthereumAddress,
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  addressToEvm,
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  evmToAddress,
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  sr25519PairFromSeed
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} from "@polkadot/util-crypto";
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// Generate Ethereum address from public key
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const seed = new Uint8Array(32);
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const pair = sr25519PairFromSeed(seed);
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const ethAddress = ethereumEncode(pair.publicKey);
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console.log(ethAddress); // "0x..."
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// Validate Ethereum address
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const isValid = isEthereumAddress("0x742d35Cc...49F8A26aE2");
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console.log(isValid); // true
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// Convert between formats
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const ss58Address = "5GrwvaEF5zXb26Fz9rcQpDWS57CtERHpNehXCPcNoHGKutQY";
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const evmBytes = addressToEvm(ss58Address);
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const backToSS58 = evmToAddress(evmBytes, 0, 'blake2');
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```