func CmpInt(x, y string) int
CmpInt returns cmp.Compare(x, y) interpreting x and y as decimal numbers. (Copied from golang.org/x/mod/semver's compareInt.)
func Compare(x, y string) int
Compare returns -1, 0, or +1 depending on whether x < y, x == y, or x > y, interpreted as toolchain versions. The versions x and y must not begin with a "go" prefix: just "1.21" not "go1.21". Malformed versions compare less than well-formed versions and equal to each other. The language version "1.21" compares less than the release candidate and eventual releases "1.21rc1" and "1.21.0".
func DecInt(decimal string) string
DecInt returns the decimal string decremented by 1, or the empty string if the decimal is all zeroes. (Copied from golang.org/x/mod/module's decDecimal.)
func IsLang(x string) bool
IsLang reports whether v denotes the overall Go language version and not a specific release. Starting with the Go 1.21 release, "1.x" denotes the overall language version; the first release is "1.x.0". The distinction is important because the relative ordering is
1.21 < 1.21rc1 < 1.21.0
meaning that Go 1.21rc1 and Go 1.21.0 will both handle go.mod files that say "go 1.21", but Go 1.21rc1 will not handle files that say "go 1.21.0".
func IsValid(x string) bool
IsValid reports whether the version x is valid.
func Lang(x string) string
Lang returns the Go language version. For example, Lang("1.2.3") == "1.2".
func Max(x, y string) string
Max returns the maximum of x and y interpreted as toolchain versions, compared using Compare. If x and y compare equal, Max returns x.
A Version is a parsed Go version: major[.Minor[.Patch]][kind[pre]] The numbers are the original decimal strings to avoid integer overflows and since there is very little actual math. (Probably overflow doesn't matter in practice, but at the time this code was written, there was an existing test that used go1.99999999999, which does not fit in an int on 32-bit platforms. The "big decimal" representation avoids the problem entirely.)
type Version struct {
Major string // decimal
Minor string // decimal or ""
Patch string // decimal or ""
Kind string // "", "alpha", "beta", "rc"
Pre string // decimal or ""
}
func Parse(x string) Version
Parse parses the Go version string x into a version. It returns the zero version if x is malformed.