Method has

modules/llrt_fetch/src/headers.rs:181–188

(&self, ctx: Ctx<'js>, key: String)

    }

    pub fn has<'js>(&self, ctx: Ctx<'js>, key: String) -> Result<bool> {
        let key = lower_key(key);
        if !is_http_header_name(&key) {
            return Err(Exception::throw_type(&ctx, "Invalid key"));
        }

        Ok(self.headers.iter().any(|(k, _)| k == &key))
    }

    pub fn set<'js>(&mut self, ctx: Ctx<'js>, key: String, value: Value<'js>) -> Result<()> {
        let key = lower_key(key);