function message(msg, actual, ...types) {
    if (types.length > 2) {
        const last = types.pop();
        msg += `one of type ${types.join(', ')}, or ${last}.`;
    }
    else if (types.length === 2) {
        msg += `one of type ${types[0]} or ${types[1]}.`;
    }
    else {
        msg += `of type ${types[0]}.`;
    }
    if (actual == null) {
        msg += ` Received ${actual}`;
    }
    else if (typeof actual === 'function' && actual.name) {
        msg += ` Received function ${actual.name}`;
    }
    else if (typeof actual === 'object' && actual != null) {
        if (actual.constructor && actual.constructor.name) {
            msg += ` Received an instance of ${actual.constructor.name}`;
        }
    }
    return msg;
}
export default (actual, ...types) => {
    return message('Key must be ', actual, ...types);
};
export function withAlg(alg, actual, ...types) {
    return message(`Key for the ${alg} algorithm must be `, actual, ...types);
}