validator

var Validator = sync.OnceValue(func() *validator.Validate {
	validator := validator.New()
	validator.RegisterValidation("floatin", floatInValidator)
	validator.RegisterValidation("choicelist", choiceListValidator)
	return validator
})

Validator is a lazily-initialised, package-level singleton of *validator.Validate. It caches struct metadata for efficiency and registers the custom validation tags "floatin" (checks a float field against a whitelist of allowed values) and "choicelist" (checks that every comma-separated token is in an allowed set).