Creating Compile-Time Reminders in Xcode
This attribute will produce a warning if the selected Swift version is available in the version of Xcode you’re using. For 5.5 for example, this would generate a warning in Xcode 13.0 but not Xcode 12.5.
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This attribute will produce a warning if the selected iOS (or tvOS, or macOS) version is equal to or below your deployment target. In other words […] after you remove support for older operating systems.
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By wrapping [a
#warning
] in this condtional compilation check, you can get Xcode to ignore the statement until you’re using an Xcode version that ships with the given compiler version.