[cplusplus] 구문 해석 좀 해주세요

 

아래 구문이 대충은 이해가 되는데 () 가 있으면 함수라는 건지  이해가 안되네요.

혹시 아시는분 댓글 부탁드려요..

https://github.com/project-chip/connectedhomeip/blob/master/src/ble/BleLayer.h

 

 

constexpr size_t kCapabilitiesResponseLength

                (kCapabilitiesResponseMagicnumLength + kCapabilitiesResponseL2capMtuLength +                                                           kCapabilitiesResponseSelectedProtocolVersionLength +  kCapabilitiesResponseWindowSizeLength);

 

 

inline constexpr size_t kCapabilitiesResponseMagicnumLength                = 2;
inline constexpr size_t kCapabilitiesResponseL2capMtuLength                = 2;
inline constexpr size_t kCapabilitiesResponseSelectedProtocolVersionLength = 1;
inline constexpr size_t kCapabilitiesResponseWindowSizeLength              = 1;
constexpr size_t kCapabilitiesResponseLength(kCapabilitiesResponseMagicnumLength + kCapabilitiesResponseL2capMtuLength +
                                             kCapabilitiesResponseSelectedProtocolVersionLength +
                                             kCapabilitiesResponseWindowSizeLength);

 

 

<사용처>

 msgBuf->SetDataLength(kCapabilitiesResponseLength);

 

 VerifyOrReturnError(msgBuf->MaxDataLength() >= kCapabilitiesResponseLength, CHIP_ERROR_NO_MEMORY);