Parse a semver string in bash using a regular expression

semver.sh

#!/usr/bin/env bash

##
# Get the major/minor/patch semver from a string.
#
# Author: Cameron Hunter <hello@cameronhunter.co.uk>
# License: MIT 2022
#
# Examples:
#		semver v14.22.1 major	→ 14
#		semver v14.22.1 minor	→ 22
#		semver v14.22.1 patch	→ 1
#		semver v14.22.1		→ 14	22	1
##
function semver {
	local string="${1}"
	local part="${2}"

	if [[ "${string}" =~ ^v?(0|[1-9][0-9]*)\.(0|[1-9][0-9]*)\.(0|[1-9][0-9]*) ]]; then
		case "${part}" in
			major) echo ${BASH_REMATCH[1]} ;;
			minor) echo ${BASH_REMATCH[2]} ;;
			patch) echo ${BASH_REMATCH[3]} ;;
			*) echo "${BASH_REMATCH[1]}\t${BASH_REMATCH[2]}\t${BASH_REMATCH[3]}" ;;
		esac
	else
		return 1
	fi
}