4 ms·

Am I the only one who found the described behavior to be intuitively correct? I did expect it to print "abc.com".

_2d30 1y ago
I don’t write Go at all but given the first example, also expected this. I was very surprised that either example compiled, though.
adastra22 1y ago
What is the intuition for that?
- binary132 1y ago
  I think it’s something like: “The general rule is that I may access the direct embeds of my type anonymously.”
  - adastra22 1y ago
    Ok I don’t think anyone disagrees with that. But there are two embedded structs, both with a URL field.
    - noisy_boy 1y ago
      But the level of nesting isn't the same; only one of them has a direct URL field.
      - masfuerte 1y ago
        You would get the same result if both URL fields were nested one level deeper. Being directly nested isn't the point.
b_e_n_t_o_n 1y ago
Yeah it makes sense to me as well.
nine_k 1y ago
This may be intuitively correct, but to my mind it is architecturally wrong. A good language should not tolerate ambiguity and offer to guess which behavior is correct.
- tayo42 1y ago
  Why is it ambiguous though? The second URL is nested Are thy not accessed like opts.URL == abc.com and opts.BarConnectionOptions.URL == xyz.com what leads you think otherwise?
  - tsimionescu 1y ago
    If there were no duplicate URL field, say they were called FooURL and BarcoURL, you could access them as `opts.FooURL` and `opts.BarcoURL`. They are both fields of `opts`, via embedding. It's just that FooURL is embedded directly, while BarcoURL is coming from two levels of embedding.
- wild_egg 1y ago
  It's not ambiguous though. The behaviour is very clearly defined in the language spec. https://go.dev/ref/spec#Selectors https://go.dev/ref/spec#Selectors As far as language specs go, Go's is really quite concise and I strongly encourage everyone I onboard to spend an afternoon reading it end to end at some point in their first couple weeks.
nvlled 1y ago
I'm confused at the responses saying this intuitive. It's like saying: var x string x = "abc.com" x = "xyz.com" fmt.Println(x) will print abc.com and that's totally expected. The normal intuition would be that the latter operations or (re)definitions override the preceding ones.
- graynk 1y ago
  It's not at all like saying that. The order of operations has nothing to do with it. opts := Options{ FooService: FooService{URL: "abc.com"}, BarService: BarService{ BarConnectionOptions: BarConnectionOptions{ URL: "xyz.com", }, }, } is equivalent to opts := Options{ BarService: BarService{ BarConnectionOptions: BarConnectionOptions{ URL: "xyz.com", }, }, FooService: FooService{URL: "abc.com"}, }
  - nvlled 1y ago
    I'm making an analogy using simple assignments to show more clearly that it's actually counter-intuitive, I'm not claiming what you seem to be refuting, which at best seems to be beside the point.
    - graynk 1y ago
      And the analogy is invalid, because it completely replaces the intuitive thing that's happening with an unintuitive thing that isn't happening. There are no "latter operations or (re)definitions" here.
      - nvlled 1y ago
        > There are no "latter operations or (re)definitions" here. Yes, in the literal narrow sense, there is no such thing in the submitted article (if it isn't already clear, I'm referring to my own example). That's why it's an analogy. I don't know the precise term that go uses for this, closest is probably "shadowing", but again it doesn't matter, it is besides the point. The point is that the exhibited behaviour is unintuitive, in contrast to what the others are saying. > it completely replaces the intuitive thing that's happening with an unintuitive thing that isn't happening What is the intuitive thing are you referring to here? If it's my example, then you are in total agreement with me, but you seem to think otherwise. If you are referring to the linked article, then you are just merely invoking tautology, to disagree with me. It's intuitive because you said so, therefore my analogy is invalid. Did I get that right?

I don’t write Go at all but given the first example, also expected this. I was very surprised that either example compiled, though.

adastra22 1y ago

What is the intuition for that?

binary132 1y ago
I think it’s something like: “The general rule is that I may access the direct embeds of my type anonymously.”
- adastra22 1y ago
  Ok I don’t think anyone disagrees with that. But there are two embedded structs, both with a URL field.
  - noisy_boy 1y ago
    But the level of nesting isn't the same; only one of them has a direct URL field.
    - masfuerte 1y ago
      You would get the same result if both URL fields were nested one level deeper. Being directly nested isn't the point.

b_e_n_t_o_n 1y ago

Yeah it makes sense to me as well.

nine_k 1y ago

This may be intuitively correct, but to my mind it is architecturally wrong. A good language should not tolerate ambiguity and offer to guess which behavior is correct.

tayo42 1y ago
Why is it ambiguous though? The second URL is nested Are thy not accessed like opts.URL == abc.com and opts.BarConnectionOptions.URL == xyz.com what leads you think otherwise?
- tsimionescu 1y ago
  If there were no duplicate URL field, say they were called FooURL and BarcoURL, you could access them as `opts.FooURL` and `opts.BarcoURL`. They are both fields of `opts`, via embedding. It's just that FooURL is embedded directly, while BarcoURL is coming from two levels of embedding.
wild_egg 1y ago
It's not ambiguous though. The behaviour is very clearly defined in the language spec. https://go.dev/ref/spec#Selectors https://go.dev/ref/spec#Selectors As far as language specs go, Go's is really quite concise and I strongly encourage everyone I onboard to spend an afternoon reading it end to end at some point in their first couple weeks.

nvlled 1y ago

I'm confused at the responses saying this intuitive. It's like saying: var x string x = "abc.com" x = "xyz.com" fmt.Println(x) will print abc.com and that's totally expected. The normal intuition would be that the latter operations or (re)definitions override the preceding ones.

graynk 1y ago
It's not at all like saying that. The order of operations has nothing to do with it. opts := Options{ FooService: FooService{URL: "abc.com"}, BarService: BarService{ BarConnectionOptions: BarConnectionOptions{ URL: "xyz.com", }, }, } is equivalent to opts := Options{ BarService: BarService{ BarConnectionOptions: BarConnectionOptions{ URL: "xyz.com", }, }, FooService: FooService{URL: "abc.com"}, }
- nvlled 1y ago
  I'm making an analogy using simple assignments to show more clearly that it's actually counter-intuitive, I'm not claiming what you seem to be refuting, which at best seems to be beside the point.
  - graynk 1y ago
    And the analogy is invalid, because it completely replaces the intuitive thing that's happening with an unintuitive thing that isn't happening. There are no "latter operations or (re)definitions" here.
    - nvlled 1y ago
      > There are no "latter operations or (re)definitions" here. Yes, in the literal narrow sense, there is no such thing in the submitted article (if it isn't already clear, I'm referring to my own example). That's why it's an analogy. I don't know the precise term that go uses for this, closest is probably "shadowing", but again it doesn't matter, it is besides the point. The point is that the exhibited behaviour is unintuitive, in contrast to what the others are saying. > it completely replaces the intuitive thing that's happening with an unintuitive thing that isn't happening What is the intuitive thing are you referring to here? If it's my example, then you are in total agreement with me, but you seem to think otherwise. If you are referring to the linked article, then you are just merely invoking tautology, to disagree with me. It's intuitive because you said so, therefore my analogy is invalid. Did I get that right?