Special constant used to denote matching any build platform.
CPU architecture identifiers, e.g. ["x86", "x86_64"]
Canonical compiler name e.g. "dmd"
Compiler binary name e.g. "ldmd2"
Compiled frontend version (e.g. 2067 for frontend versions 2.067.x)
Platform identifiers, e.g. ["posix", "windows"]
Represents a platform a package can be build upon.