package validate var ( ErrMustBeLonger = NewError("must contain at least %d characters") ErrMustBeShorter = NewError("must contain no more than %d characters") ) // MaxLength validates that a string is no longer than a given maximum. // Length is measured in bytes (len), not runes. func MaxLength(l int) func(string) error { return func(value string) error { if len(value) > l { return ErrMustBeShorter.With(l) } return nil } } // MinLength validates that a string is at least a given minimum length. // Length is measured in bytes (len), not runes. func MinLength(l int) func(string) error { return func(value string) error { if len(value) < l { return ErrMustBeLonger.With(l) } return nil } }