@nktkas/hyperliquid/esm/src/signing/_ethers.js

Unofficial Hyperliquid API SDK for all major JS runtimes, written in TypeScript and provided with tests

/** Checks if the given value is an abstract ethers signer. */
export function isAbstractEthersSigner(client) {
    return typeof client === "object" && client !== null &&
        "signTypedData" in client && typeof client.signTypedData === "function" &&
        client.signTypedData.length === 3;
}
/** Checks if the given value is an abstract ethers v5 signer. */
export function isAbstractEthersV5Signer(client) {
    return typeof client === "object" && client !== null &&
        "_signTypedData" in client && typeof client._signTypedData === "function" &&
        client._signTypedData.length === 3;
}