func compare(st px.ParsexState) (interface{}, error) {
l, err := px.Bind(px.Choice(
px.Bind(IntValue, LessThanNumber),
px.Bind(NumberValue, LessThanFloat),
px.Bind(px.StringVal, LessThanString),
px.Bind(TimeValue, LessThanTime),
), func(l interface{}) px.Parser {
return func(st px.ParsexState) (interface{}, error) {
_, err := px.Eof(st)
if err != nil {
return nil, ParsexSignErrorf("less args sign error: except eof")
}
return l, nil
}
})(st)
if err == nil {
return l, nil
}
return nil, ParsexSignErrorf("Except two lessable values compare but error %v", err)
}
// return false, true or nil
func lessOption(env Env) px.Parser {
return func(st px.ParsexState) (interface{}, error) {
l, err := px.Bind(px.Choice(
px.Try(px.Bind(IntValue, LessThanNumber)),
px.Try(px.Bind(NumberValue, LessThanFloat)),
px.Try(px.Bind(px.StringVal, LessThanString)),
px.Try(px.Bind(TimeValue, LessThanTime)),
px.Try(px.Bind(ListValue, LessThanListOption(env))),
px.Bind(px.AnyOne, LessThanNil),
), func(l interface{}) px.Parser {
return func(st px.ParsexState) (interface{}, error) {
_, err := px.Eof(st)
if err != nil {
return nil, ParsexSignErrorf("less args sign error: except eof")
}
return l, nil
}
})(st)
if err == nil {
return l, nil
}
return nil, ParsexSignErrorf("Except two lessable values or nil compare but error: %v", err)
}
}