fish-shell/share/functions/__fish_seen_argument.fish

function __fish_seen_argument
	argparse 's/short=+' 'l/long=+' -- $argv

	set cmd (commandline -co)
	set -e cmd[1]
	for t in $cmd
		for s in $_flag_s
			if string match -qr "^-[A-z0-9]*"$s"[A-z0-9]*\$" -- $t
				return 0
			end
		end

		for l in $_flag_l
			if string match -q -- "--$l" $t
				return 0
			end
		end
	end

	return 1
end