有没有获取当前命名空间和函数名称的C宏？例：
namespace foo {
namespace bar {
void baz(int i,double d) {
std::cout << MACRO << std::endl;
}
}
}
会打印foo :: bar :: baz.我知道__FUNCTION__但是它不给出命名空间.并且BOOST_CURRENT_FUNCTION给出整个签名,包括.参数和返回类型：
void foo::bar::baz(int,double)
也许,是否可以编写从BOOST_CURRENT_FUNCTION中提取命名空间和函数名的宏？
我想要用于记录目的,获取一个日志字符串
foo::bar::baz -- blah logging message blah
解决方法
据我所知,这是不可能的(不可移植的).但是从完整的签名可以提取这些参数.当然,它需要解析所述签名,这不是那么容易：x
这是我现在使用的功能：
// What we want to consume:
// void
// signed short
// unsigned int
// Test::Bar<T,N>
//
static char const* consumeType(char const* const begin,char const* const end){
static StringRef const Signed("signed");
static StringRef const Unsigned("unsigned");
char const* it = begin;
if (startsWith(it,Signed)) { it += Signed.size() + 1; }
else if (startsWith(it,Unsigned)) { it += Unsigned.size() + 1; }
// jump over the return type
size_t templateNest = 0;
while (it != end) {
if (*it == ' ' and templateNest == 0) { break; }
if (*it == '<') { ++templateNest; }
if (*it == '>' and templateNest > 0) { --templateNest; }
++it;
}
return it;
} // consumeType
//
// \param signature: signature as returned by __func___ on gcc
// \return: full name,included namespace qualifier and class (if any)
//
// void Test::Bar<T,N>::parameterized(U) const
// [with unsigned int O = 4u,U = Test::Foo,// T = Test::Foo,unsigned int N = 3u]
// -> Test::Bar<T,N>::parameterized
//
StringRef parseFunctionName(StringRef const signature) {
char const* begin = signature.begin();
char const* end = signature.end();
// Jump over the return type
begin = consumeType(begin,end);
if (begin == end) { return signature; }
// skip the space right after the return type
++begin;
if (begin == end) { return signature; }
// if we encounter a '(' then it means that we return a function,// and we once again need to jump over the return type
if (*begin == '(') {
begin = consumeType(++begin,end);
// skip the space
++begin;
if (begin == end) { return signature; }
}
// and finally,we got the beginning,and we need to get the end,which is
// the first opening '('
char const* e = std::find(begin,end,'(');
return StringRef(begin,e - begin);
} // parseFunctionName
及其伴随测试：
#define UT_FUNCTION_CHECK(Signature_,Name_) \
UT_CHECK(parseFunctionName(StringRef(Signature_)) == Name_);
void Function() {
// Regular functions
UT_FUNCTION_CHECK("int main()","main")
UT_FUNCTION_CHECK("int foo(int,double)","foo")
UT_FUNCTION_CHECK("unsigned int foo(int,"foo")
// Templates
UT_FUNCTION_CHECK("unsigned int Test::Bar<T,N>::print() const"
" [with T = Test::Foo,unsigned int N = 3u]","Test::Bar<T,N>::print")
UT_FUNCTION_CHECK("Test::Bar<T,N> Test::Bar<T,N>::print")
UT_FUNCTION_CHECK("void Test::Bar<T,N>::parameterized(U) const"
" [with unsigned int O = 4u,"
" T = Test::Foo,N>::parameterized")
// Functions returning functions
UT_FUNCTION_CHECK("void (* Test::Foo::func() const)()","Test::Foo::func")
UT_FUNCTION_CHECK("void (Test::Foo::* Test::Foo::method() const)(int)volatile","Test::Foo::method")
UT_FUNCTION_CHECK("void (Test::Foo::* Test::Foo::super())"
"(void (Test::Foo::*)(int)volatile)const","Test::Foo::super")
} // Function
它与gcc的__func__宏结合使用.
StringRef类与llvm::StringRef类似.
如果您能负担额外的解析,我认为它应该满足您的需求.这是非常快的：没有回溯和没有动态分配,所以不应该是一个问题(尤其是写入一个文件…).
希望它有帮助.
