#if targetEnvironment(macCatalyst)
print("Launch on Mac")
#elseif targetEnvironment(simulator)
print("Launch on simulator")
#else
print("Launch on iOS")
#endif
| Platform condition | Valid arguments |
| os() | macOS, iOS, watchOS, tvOS, visionOS, Linux, Windows |
| arch() | i386, x86_64, arm, arm64 |
| swift() | >= or < followed by a version number |
| compiler() | >= or < followed by a version number |
| canImport() | A module name |
| targetEnvironment() | simulator, macCatalyst |
| A conditional compilation block allows code to be conditionally compiled depending on the value of one or more compilation conditions. Every conditional compilation block begins with the #if compilation directive and ends with the #endif compilation directive. |