You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: semver.go
    path of file: ./repos/kubeedge/vendor/github.com/blang/semver/v4
    
    the code of the file until where you have to start completion: package semver

import (
	"errors"
	"fmt"
	"strconv"
	"strings"
)

const (
	numbers  string = "0123456789"
	alphas      
    
func (v Version) Compare(o Version) int {
	if v.Major != o.Major {
		if v.Major > o.Major {
			return 1
		}
		return -1
	}
	if v.Minor != o.Minor {
		if v.Minor > o.Minor {
			return 1
		}
		return -1
	}
	if v.Patch != o.Patch {
		if v.Patch > o.Patch {
			return 1
		}
		return -1
	}

	// Quick comparison if a version has no prerelease versions
	if len(v.Pre) == 0 && len(o.Pre) == 0 {
		return 0
	} else if len(v.Pre) == 0 && len(o.Pre) > 0 {
		return 1
	} else if len(v.Pre) > 0 && len(o.Pre) == 0 {
		return -1
	}

	i := 0
	for ; i < len(v.Pre) && i < len(o.Pre); i++ {
		if comp := v.Pre[i].Compare(o.Pre[i]); comp == 0 {
			continue
		} else if comp == 1 {
			return 1
		} else {
			return -1
		}
	}

	// If all pr versions are the equal but one has further prversion, this one greater
	if i == len(v.Pre) && i == len(o.Pre) {
		return 0
	} else if i == len(v.Pre) && i < len(o.Pre) {
		return -1
	} else {
		return 1
	}

}