_macOSVersion

Parse the version number as with getOSVersion and then translate generic “darwin” versions to the corresponding OS X versions. This may also be called with IOS triples but the OS X version number is just set to a constant 10.4.0 in that case.

Triple.swift:1571
var _macOSVersion: Version? { get }

Returns true if successful.

This accessor is semi-private; it’s typically better to use version(for:) or Triple.FeatureAvailability.