macro_rules! impl_contract {
($struct_name:ident) => {
impl $struct_name {
pub fn new(api_key: Option<String>, api_secret: Option<String>) -> Self {
Self { _api_key: api_key, _api_secret: api_secret }
}
pub fn fetch_trades(symbol: &str) -> Result<String> {
gen_api!(format!("/market/history/trade?symbol={}&size=2000", symbol))
}
}
};
}