我正在使用#define
定义一组参数,以便稍后可以在main()
中调用定义的名称。但是,我在第1行中出现了“ expected expression before '{' token
”。我想知道我的语法是否错误。
#define ADV_1M_LEGACY_CONNECTABLE { \
.properties.type = BLE_GAP_ADV_TYPE_CONNECTABLE_SCANNABLE_UNDIRECTED, \
.p_peer_addr = NULL, \
.interval = APP_ADV_INTERVAL, \
.duration = APP_ADV_DURATION, \
.max_adv_evts = 0, \
.channel_mask = 0, \
.filter_policy = BLE_GAP_ADV_FP_ANY, \
.primary_phy = BLE_GAP_PHY_1MBPS, \
.secondary_phy = 0, \
.set_id = 0, \
.scan_req_notification = 0 \
}
来自评论:
我有一个调用函数:
m_adv_handle = advertising_init_common(&m_adv_data, ADV_1M_LEGACY_CONNECTABLE);
编辑代码后,在此调用行中,出现错误“
expected expression before ')' token
”。
已更新:
typedef struct
{
ble_gap_adv_properties_t properties;
ble_gap_addr_t const *p_peer_addr;
uint32_t interval;
uint16_t duration;
uint8_t max_adv_evts;
ble_gap_ch_mask_t channel_mask;
uint8_t filter_policy;
uint8_t primary_phy;
uint8_t secondary_phy;
uint8_t set_id:4;
uint8_t scan_req_notification:1;
}ble_gap_adv_params_t; //******this being declare in another .h file
#define ADV_1M_LEGACY_CONNECTABLE (ble_gap_adv_params_t) { \
.properties.type = BLE_GAP_ADV_TYPE_CONNECTABLE_SCANNABLE_UNDIRECTED, \
.p_peer_addr = NULL, \
.interval = APP_ADV_INTERVAL, \
.duration = APP_ADV_DURATION, \
.max_adv_evts = 0, \
.channel_mask = 0, \
.filter_policy = BLE_GAP_ADV_FP_ANY, \
.primary_phy = BLE_GAP_PHY_1MBPS, \
.secondary_phy = 0, \
.set_id = 0, \
.scan_req_notification = 0 \
}
static uint8_t advertising_init_common(ble_gap_adv_data_t*
ble_gap_adv_data, ble_gap_adv_params_t adv_params)
{
ret_code_t err_code;
ble_advdata_t advdata;
ble_advdata_t srdata;
uint8_t advHandle;
ble_uuid_t adv_uuids[] = {{LBS_UUID_SERVICE, m_lbs.uuid_type}};`
// Build and set advertising data.
memset(&ble_gap_adv_data->adv_data, 0, sizeof(ble_gap_adv_data->adv_data));
advdata.name_type = BLE_ADVDATA_FULL_NAME;
advdata.include_appearance = true;
advdata.flags = BLE_GAP_ADV_FLAGS_LE_ONLY_GENERAL_DISC_MODE;
memset(&srdata, 0, sizeof(srdata));
srdata.uuids_complete.uuid_cnt = sizeof(adv_uuids) / sizeof(adv_uuids[0]);
srdata.uuids_complete.p_uuids = adv_uuids;
err_code = ble_advdata_encode(&advdata, ble_gap_adv_data->adv_data.p_data, &ble_gap_adv_data->adv_data.len);
APP_ERROR_CHECK(err_code);
err_code = ble_advdata_encode(&srdata, ble_gap_adv_data->scan_rsp_data.p_data, &ble_gap_adv_data->scan_rsp_data.len);
APP_ERROR_CHECK(err_code);
// Set advertising parameters.
err_code = sd_ble_gap_adv_set_configure(&advHandle, ble_gap_adv_data,
&adv_params);
APP_ERROR_CHECK(err_code);
return advHandle;
}
int main()
{
m_adv_handle = advertising_init_common(&m_adv_data,
ADV_1M_LEGACY_CONNECTABLE); //*********here i have "expected expression before ')' token message*******//
}
所以我想知道我又在哪里做错了。可以指导我吗?谢谢
答案 0 :(得分:1)
您需要提供一种类型以及C99
compound literal。
typedef struct conn_s { /*...*/ } conn_t;
#define ADV_1M_LEGACY_CONNECTABLE (conn_t){ /*...*/ }
int main() {
conn_t conn = ADV_1M_LEGACY_CONNECTABLE;
}
这里是example。
答案 1 :(得分:1)
这太大了,无法发表评论,因此是伪答案。
这是MCVE的近似值-存在一个重大问题,当我编译它时,看不到您看到的错误。
arm31.cpp
#include <cstdint>
typedef struct
{
uint32_t interval;
uint16_t duration;
uint8_t max_adv_evts;
uint8_t secondary_phy;
} ble_gap_adv_params_t;
typedef struct
{
ble_gap_adv_params_t adv_params;
uint16_t adv_program;
} ble_gap_adv_data_t;
#define ADV_1M_LEGACY_CONNECTABLE (ble_gap_adv_params_t) { \
.interval = 29, \
.duration = 31, \
.max_adv_evts = 0, \
.secondary_phy = 0, \
}
static uint8_t advertising_init_common(ble_gap_adv_data_t *ble_gap_adv_data,
ble_gap_adv_params_t adv_params)
{
uint8_t advHandle = 19;
ble_gap_adv_data->adv_params = adv_params;
ble_gap_adv_data->adv_program = 31963;
return advHandle;
}
#include <iostream>
int main()
{
ble_gap_adv_data_t m_adv_data;
uint8_t m_adv_handle = advertising_init_common(&m_adv_data,
ADV_1M_LEGACY_CONNECTABLE);
std::cout
<< "handle: " << m_adv_handle << ", "
<< "program: " << m_adv_data.adv_program << ", "
<< "interval: " << m_adv_data.adv_params.interval << ", "
<< "duration: " << m_adv_data.adv_params.duration << ", "
<< "maxadvev: " << m_adv_data.adv_params.max_adv_evts << ", "
<< "secondph: " << m_adv_data.adv_params.secondary_phy << "\n";
}
$ g++ -O3 -g -std=c++11 -Wall -Wextra -Werror -c arm31.cpp
$
不会产生任何警告(在使用自制G ++ 8.2.0的运行macOS 10.14.2 Mojave的Mac上)。要获取警告,我也需要使用-pedantic
:
$ g++ -O3 -g -std=c++11 -Wall -Wextra -Werror -pedantic -c arm31.cpp
arm31.cpp: In function ‘int main()’:
arm31.cpp:18:9: error: C++ designated initializers only available with -std=c++2a or -std=gnu++2a [-Werror=pedantic]
.interval = 29, \
^
arm31.cpp:39:52: note: in expansion of macro ‘ADV_1M_LEGACY_CONNECTABLE’
ADV_1M_LEGACY_CONNECTABLE);
^~~~~~~~~~~~~~~~~~~~~~~~~
arm31.cpp:19:9: error: C++ designated initializers only available with -std=c++2a or -std=gnu++2a [-Werror=pedantic]
.duration = 31, \
^
arm31.cpp:39:52: note: in expansion of macro ‘ADV_1M_LEGACY_CONNECTABLE’
ADV_1M_LEGACY_CONNECTABLE);
^~~~~~~~~~~~~~~~~~~~~~~~~
arm31.cpp:20:9: error: C++ designated initializers only available with -std=c++2a or -std=gnu++2a [-Werror=pedantic]
.max_adv_evts = 0, \
^
arm31.cpp:39:52: note: in expansion of macro ‘ADV_1M_LEGACY_CONNECTABLE’
ADV_1M_LEGACY_CONNECTABLE);
^~~~~~~~~~~~~~~~~~~~~~~~~
arm31.cpp:21:9: error: C++ designated initializers only available with -std=c++2a or -std=gnu++2a [-Werror=pedantic]
.secondary_phy = 0, \
^
arm31.cpp:39:52: note: in expansion of macro ‘ADV_1M_LEGACY_CONNECTABLE’
ADV_1M_LEGACY_CONNECTABLE);
^~~~~~~~~~~~~~~~~~~~~~~~~
arm31.cpp:22:1: error: ISO C++ forbids compound-literals [-Werror=pedantic]
}
^
arm31.cpp:39:52: note: in expansion of macro ‘ADV_1M_LEGACY_CONNECTABLE’
ADV_1M_LEGACY_CONNECTABLE);
^~~~~~~~~~~~~~~~~~~~~~~~~
cc1plus: all warnings being treated as errors
请获取此源代码并将其在您的系统上编译。然后修改它,直到它再现您所看到的错误。然后将修改后的代码发布为问题的编辑。