┌─────────────────────────────────────────────────────────────┐
│ NAMESPACE RESOLUTION │
├─────────────────────────────────────────────────────────────┤
│ Core::Network::Socket ──► Belongs to Network subsystem │
│ Core::Audio::Socket ──► Distinct symbol, no collision! │
└─────────────────────────────────────────────────────────────┘namespace { int localVal = 10; } grants the identifiers internal linkage, making them private to the current .cpp file (modern C++ alternative to static global variables).
#include <iostream>
#include <string>
// Nested Namespace (C++17 syntax)
namespace App::Security {
class Authenticator {
public:
static bool verifyToken(const std::string& token) {
return !token.empty() && token.rfind("SEC-", 0) == 0;
}
};
}
// Anonymous Namespace for translation-unit local helper
namespace {
void logInternal(const std::string& msg) {
std::cout << "[Private Internal Log] " << msg << "\n";
}
}
int main() {
std::string token = "SEC-ALPHA-909";
if (App::Security::Authenticator::verifyToken(token)) {
logInternal("Access granted with valid security token.");
} else {
logInternal("Access denied.");
}
return 0;
}using namespace ...; in header files.namespace sec = App::Security;) to shorten deeply nested namespace names..cpp files instead of C-style static global functions.